Getting a timer to go to 0

Hey everyone,

What i'm trying to do is after the timer goes to 0 i'd like for the timer to stop for 2 seconds and then reset and thus the process will repeat. What i have so far is...

     public GUIText timerText;
     public float timer = 0.0f;
     public float timerMax;
 
     void Start()
     {
         timer = timerMax ;
     }
 
     void Update()
     {
         if (timer <= 0.0f)
         {
             StartCoroutine(wait(2.0f));
             timer = timerMax;
         }
 
         else
         {
             countdown();
         }
     }
 
     void countdown()
     {
         timer -= Time.deltaTime;
         updateTimerText();
     }
 
     IEnumerator wait(float waitTimer)
     {
         yield return new WaitForSeconds(waitTimer);
     }
 
     void updateTimerText()
     {
         timerText.text = "Timer: \n" + Mathf.Round(timer * 10f) / 10f;
     }

This is also used with a GUIText to print out the timer but that shouldn't really matter. The issue at the moment is that it's not stopping for the 2 seconds. I think this might be due to it not reaching 0 but then again the timer does reset so i'm not too certain.

Any help will be appreciated!