Assertion failed on expression: 'changeMask != 0'

today all out of the sudden this error came. i was doing some basic stuff what i did before and this error apeared. i was making a stocks shower for my custom dashboard and it works but and could not find a problem in my script. i hope you guys can help me. thanks in advance. NOTE: im using Unity 5.6.0b3

using UnityEngine;
using UnityEngine.UI;
using System.Xml;
using System.Collections;
public class Stocks : MonoBehaviour {
    string AEXurl;
    string Microsofturl; string Appleurl; string Googleurl;
    string Intelurl; string Nvidiaurl; string AMDurl;
    string EAurl; string Blizzardurl; string Ubisofturl;
    WWW wwwAEX;
    WWW wwwMicrosoft; WWW wwwApple; WWW wwwGoogle;
    WWW wwwIntel; WWW wwwNvidia; WWW wwwAMD;
    WWW wwwEA; WWW wwwBlizzard; WWW wwwUbisoft;
    Animation anim;
    GameObject Stocks1; GameObject Stocks2; GameObject Stocks3;
    Text Stocks1Name; Text Stocks1Price; Text Stocks1Change;
    Text Stocks2Name; Text Stocks2Price; Text Stocks2Change;
    Text Stocks3Name; Text Stocks3Price; Text Stocks3Change;
    void Start () {
        AEXurl = "https://query.yahooapis.com/v1/public/yql?q=select%20*%20from%20yahoo.finance.quotes%20where%20symbol%20in%20(%22%5EAEX%22)&diagnostics=true&env=http%3A%2F%2Fdatatables.org%2Falltables.env";
        Microsofturl = "https://query.yahooapis.com/v1/public/yql?q=select%20*%20from%20yahoo.finance.quotes%20where%20symbol%20in%20(%22MSFT%22)&diagnostics=true&env=http%3A%2F%2Fdatatables.org%2Falltables.env";
        Appleurl = "https://query.yahooapis.com/v1/public/yql?q=select%20*%20from%20yahoo.finance.quotes%20where%20symbol%20in%20(%22AAPL%22)&diagnostics=true&env=http%3A%2F%2Fdatatables.org%2Falltables.env";
        Googleurl = "https://query.yahooapis.com/v1/public/yql?q=select%20*%20from%20yahoo.finance.quotes%20where%20symbol%20in%20(%22GOOGL%22)&diagnostics=true&env=http%3A%2F%2Fdatatables.org%2Falltables.env";
        Intelurl = "https://query.yahooapis.com/v1/public/yql?q=select%20*%20from%20yahoo.finance.quotes%20where%20symbol%20in%20(%22INTC%22)&diagnostics=true&env=http%3A%2F%2Fdatatables.org%2Falltables.env";
        Nvidiaurl = "https://query.yahooapis.com/v1/public/yql?q=select%20*%20from%20yahoo.finance.quotes%20where%20symbol%20in%20(%22NVDA%22)&diagnostics=true&env=http%3A%2F%2Fdatatables.org%2Falltables.env";
        AMDurl = "https://query.yahooapis.com/v1/public/yql?q=select%20*%20from%20yahoo.finance.quotes%20where%20symbol%20in%20(%22AMD%22)&diagnostics=true&env=http%3A%2F%2Fdatatables.org%2Falltables.env";
        EAurl = "https://query.yahooapis.com/v1/public/yql?q=select%20*%20from%20yahoo.finance.quotes%20where%20symbol%20in%20(%22EA%22)&diagnostics=true&env=http%3A%2F%2Fdatatables.org%2Falltables.env";
        Blizzardurl = "https://query.yahooapis.com/v1/public/yql?q=select%20*%20from%20yahoo.finance.quotes%20where%20symbol%20in%20(%22ATVI%22)&diagnostics=true&env=http%3A%2F%2Fdatatables.org%2Falltables.env";
        Ubisofturl = "https://query.yahooapis.com/v1/public/yql?q=select%20*%20from%20yahoo.finance.quotes%20where%20symbol%20in%20(%22UEN.F%22)&diagnostics=true&env=http%3A%2F%2Fdatatables.org%2Falltables.env";
        anim = GameObject.Find("Stocks").GetComponent<Animation>();
        Stocks1 = GameObject.Find("Stocks1");
        Stocks2 = GameObject.Find("Stocks2");
        Stocks3 = GameObject.Find("Stocks3");
        Stocks1Name = GameObject.Find("Stocks1Name").GetComponent<Text>();
        Stocks1Price = GameObject.Find("Stocks1Price").GetComponent<Text>();
        Stocks1Change = GameObject.Find("Stocks1Change").GetComponent<Text>();
        Stocks2Name = GameObject.Find("Stocks2Name").GetComponent<Text>();
        Stocks2Price = GameObject.Find("Stocks1Price").GetComponent<Text>();
        Stocks2Change = GameObject.Find("Stocks1Change").GetComponent<Text>();
        Stocks3Name = GameObject.Find("Stocks3Name").GetComponent<Text>();
        Stocks3Price = GameObject.Find("Stocks1Price").GetComponent<Text>();
        Stocks3Change = GameObject.Find("Stocks1Change").GetComponent<Text>();
        StartCoroutine("Round1");
    }
    IEnumerator Round1() {
        wwwAEX = new WWW(AEXurl);
        yield return wwwAEX;
        XmlDocument xmlAEX = new XmlDocument(); xmlAEX.LoadXml(wwwAEX.text);
        if (wwwAEX.error == null) {
            Stocks1Name.text = "AEX";
            Stocks1Price.text = xmlAEX.SelectSingleNode("query/results/quote/LastTradePriceOnly").InnerText;
            Stocks1Change.text = xmlAEX.SelectSingleNode("query/results/quote/Change").InnerText + " (" +
                                    xmlAEX.SelectSingleNode("query/results/quote/ChangeinPercent").InnerText + ")";
            Stocks2.SetActive(false);
            Stocks3.SetActive(false);
            anim.Play("StocksUp");
            yield return new WaitForSeconds(10);
            anim.Play("StocksDown");
            StartCoroutine("Round2");
        }
        else { print("Error Round1"); }
    }
    IEnumerator Round2() {
        wwwMicrosoft = new WWW(Microsofturl); wwwApple = new WWW(Appleurl); wwwGoogle = new WWW(Googleurl);
        yield return wwwMicrosoft; yield return wwwApple; yield return wwwGoogle;
        XmlDocument xmlMicrosoft = new XmlDocument(); xmlMicrosoft.LoadXml(wwwMicrosoft.text);
        XmlDocument xmlApple = new XmlDocument(); xmlApple.LoadXml(wwwApple.text);
        XmlDocument xmlGoogle = new XmlDocument(); xmlGoogle.LoadXml(wwwGoogle.text);
        if (wwwMicrosoft.error == null && wwwApple.error == null && wwwGoogle.error == null) {
            Stocks1Name.text = "Microsoft";
            Stocks1Price.text = xmlMicrosoft.SelectSingleNode("query/results/quote/LastTradePriceOnly").InnerText;
            Stocks1Change.text = xmlMicrosoft.SelectSingleNode("query/results/quote/Change").InnerText + " (" +
                                    xmlMicrosoft.SelectSingleNode("query/results/quote/ChangeinPercent").InnerText + ")";
            Stocks2Name.text = "Apple";
            Stocks2Price.text = xmlApple.SelectSingleNode("query/results/quote/LastTradePriceOnly").InnerText;
            Stocks2Change.text = xmlApple.SelectSingleNode("query/results/quote/Change").InnerText + " (" +
                                    xmlApple.SelectSingleNode("query/results/quote/ChangeinPercent").InnerText + ")";
            Stocks3Name.text = "Google";
            Stocks3Price.text = xmlGoogle.SelectSingleNode("query/results/quote/LastTradePriceOnly").InnerText;
            Stocks3Change.text = xmlGoogle.SelectSingleNode("query/results/quote/Change").InnerText + " (" +
                                    xmlGoogle.SelectSingleNode("query/results/quote/ChangeinPercent").InnerText + ")";
            Stocks2.SetActive(true);
            Stocks3.SetActive(true);
            anim.Play("StocksUp");
            yield return new WaitForSeconds(10);
            anim.Play("StocksDown");
            StartCoroutine("Round3");
        }
        else { print("Error Round2"); }
    }
    IEnumerator Round3() {
        wwwIntel = new WWW(Intelurl); wwwNvidia = new WWW(Nvidiaurl); wwwAMD = new WWW(AMDurl);
        yield return wwwIntel; yield return wwwNvidia; yield return wwwAMD;
        XmlDocument xmlIntel = new XmlDocument(); xmlIntel.LoadXml(wwwIntel.text);
        XmlDocument xmlNvidia = new XmlDocument(); xmlNvidia.LoadXml(wwwNvidia.text);
        XmlDocument xmlAMD = new XmlDocument(); xmlAMD.LoadXml(wwwAMD.text);
        if (wwwIntel.error == null && wwwNvidia.error == null && wwwAMD.error == null) {
            Stocks1Name.text = "Intel";
            Stocks1Price.text = xmlIntel.SelectSingleNode("query/results/quote/LastTradePriceOnly").InnerText;
            Stocks1Change.text = xmlIntel.SelectSingleNode("query/results/quote/Change").InnerText + " (" +
                                    xmlIntel.SelectSingleNode("query/results/quote/ChangeinPercent").InnerText + ")";
            Stocks2Name.text = "Nvidia";
            Stocks2Price.text = xmlNvidia.SelectSingleNode("query/results/quote/LastTradePriceOnly").InnerText;
            Stocks2Change.text = xmlNvidia.SelectSingleNode("query/results/quote/Change").InnerText + " (" +
                                    xmlNvidia.SelectSingleNode("query/results/quote/ChangeinPercent").InnerText + ")";
            Stocks3Name.text = "AMD";
            Stocks3Price.text = xmlAMD.SelectSingleNode("query/results/quote/LastTradePriceOnly").InnerText;
            Stocks3Change.text = xmlAMD.SelectSingleNode("query/results/quote/Change").InnerText + " (" +
                                    xmlAMD.SelectSingleNode("query/results/quote/ChangeinPercent").InnerText + ")";
            anim.Play("StocksUp");
            yield return new WaitForSeconds(10);
            anim.Play("StocksDown");
            StartCoroutine("Round4");
        }
        else { print("Error Round3"); }
    }
    IEnumerator Round4() {
        wwwEA = new WWW(EAurl); wwwBlizzard = new WWW(Blizzardurl); wwwUbisoft = new WWW(Ubisofturl);
        yield return wwwEA; yield return wwwBlizzard; yield return wwwUbisoft;
        XmlDocument xmlEA = new XmlDocument(); xmlEA.LoadXml(wwwEA.text);
        XmlDocument xmlBlizzard = new XmlDocument(); xmlBlizzard.LoadXml(wwwBlizzard.text);
        XmlDocument xmlUbisoft = new XmlDocument(); xmlUbisoft.LoadXml(wwwUbisoft.text);
        if (wwwEA.error == null && wwwBlizzard.error == null && wwwUbisoft.error == null) {
            Stocks1Name.text = "EA";
            Stocks1Price.text = xmlEA.SelectSingleNode("query/results/quote/LastTradePriceOnly").InnerText;
            Stocks1Change.text = xmlEA.SelectSingleNode("query/results/quote/Change").InnerText + " (" +
                                    xmlEA.SelectSingleNode("query/results/quote/ChangeinPercent").InnerText + ")";
            Stocks2Name.text = "Blizzard";
            Stocks2Price.text = xmlBlizzard.SelectSingleNode("query/results/quote/LastTradePriceOnly").InnerText;
            Stocks2Change.text = xmlBlizzard.SelectSingleNode("query/results/quote/Change").InnerText + " (" +
                                    xmlBlizzard.SelectSingleNode("query/results/quote/ChangeinPercent").InnerText + ")";
            Stocks3Name.text = "Ubisoft";
            Stocks3Price.text = xmlUbisoft.SelectSingleNode("query/results/quote/LastTradePriceOnly").InnerText;
            Stocks3Change.text = xmlUbisoft.SelectSingleNode("query/results/quote/Change").InnerText + " (" +
                                    xmlUbisoft.SelectSingleNode("query/results/quote/ChangeinPercent").InnerText + ")";
            anim.Play("StocksUp");
            yield return new WaitForSeconds(10);
            anim.Play("StocksDown");
            StartCoroutine("Round1");
        }
        else { print("Error Round4"); }
    }
}

This problem is occurs during animation playback in beta version.
The problem will fixed in 5.6.0(Release version).