Increase a value by one every minute

I’m trying to increase a value by one every 60 seconds. This is what I got so far:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;

public class DayCounter : MonoBehaviour {

public Text secondsText;
public Text dayText;
int day;
float seconds;

void Start ()
{       
    seconds = PlayerPrefs.GetFloat("Seconds Text", 0);
    secondsText.text = "Seconds: " + seconds.ToString("00");

    day = PlayerPrefs.GetInt("Day Text", 0);
    dayText.text = "Day: " + day;
}

void Update ()
{
    seconds = (int)(Time.time % 60f);
    secondsText.text = "Seconds: " + seconds.ToString("00");
   
    if (seconds >= 5)
    {
        day++;
        seconds = 0;
        secondsText.text = "Seconds: " + seconds.ToString("00");            
        dayText.text = "Day: " + day;

        Debug.Log("a day has passed");
    }
}

**the 5 seconds mark and the seconds display are just for testing **

The text display works fine. The problem is that after 5 seconds, the seconds counter gets stuck on zero, and the days counter keeps increasing forever.

I want a script that doesn’t show the seconds display ingame, and increases the value of the Day variable by one every minute.

Any help would be appreciated ^^

Use Coroutines:

public int day;

void Start  () {
	day = 0;
	StartCoroutine(Timer(60));
}

IEnumerator Timer(int time) {
	yield return WaitForSeconds(time);
	day++;
	seconds = 0;
    secondsText.text = "Seconds: " + seconds.ToString("00");            
    dayText.text = "Day: " + day;
    Debug.Log("a day has passed");
}

I figured out how to do it using this post: c# - Increase variable x amount every x seconds - Stack Overflow

The final script looks like this:

public class DayCounter : MonoBehaviour {

public Text secondsText;
public Text dayText;
int day;
public int dayMark;
float seconds;

void Start ()
{       
    seconds = PlayerPrefs.GetFloat("Seconds Text", 0);
    secondsText.text = "Seconds: " + seconds.ToString("00");

    day = PlayerPrefs.GetInt("Day Text", 0);
    dayText.text = "Day: " + day;
}

void Update ()
{
    seconds += Time.deltaTime;
    secondsText.text = "Seconds: " + seconds.ToString("00");
    if(seconds >= dayMark)
    {
        DayCount();
        dayText.text = "Day: " + day;
        seconds = 0;
    }      
}

void DayCount()
{
    day++;
}

}