after pressing button many times the player starts moving more.

Hello, I am pretty new to unity and I am currently making my first game. So today i made two buttons which control the player. One button is for moving up and the other one is for moving down. I made a script for these buttons and my problem is that if I press one of the buttons more than one time then the player starts moving more. (Sorry for my bad english). So if i press the button second time then the vector 3 that should be playyer.transform.position += new Vector3 (0,-0.2f* Time.deltaTime ,0); it goes to something like that playyer.transform.position += new Vector3 (0,-2f* Time.deltaTime ,0); , the y increases every time i press the button.

using UnityEngine;
using System.Collections;
using UnityEngine.UI;
public class proov : MonoBehaviour {
	public Button ules;
	public GameObject playyer;
	public Button alla;

	// Use this for initialization
	void Start () {

	}

	// Update is called once per frame
	void Update () {
		ules.onClick.AddListener (() => {
			playyer.transform.position += new Vector3 (0, 0.2f *Time.deltaTime , 0);
		});

		alla.onClick.AddListener (() => {
			playyer.transform.position += new Vector3 (0,-0.2f* Time.deltaTime ,0);
		});


	
	
	}
			}

Thanks for reading and sorry for my bad English.

You are repeating the event registration, you should only register once in OnEnable(), you also need to cancel the registration in OnDisable().