Unexpected text appears using UI

I'm creating my very first game in which a ball is repairing objects. When I enter the collider of an object, a text appears under the simple minimap saying "In repair..." with a countdown and when the countdown is over, it turns into "REPAIRED". This is all good, but when I enter the collider for the 2nd time before OR after it is repaired, the following strange, upside-down text appears for a very brief time (couple of frames maybe): No text should appear here.

In comparison, this is what I should normally see (and I do see it after a frame, please disregard the glowing element, it is not connected to the text): I paste the script controlling the behavior of the text here :

 using UnityEngine;
 using System.Collections;
 using UnityEngine.UI;
 
     public class RepairText : MonoBehaviour {
     public Text repairText; //reference to the text comp
     public GameObject metaBallTrigger; // reference to the GO trigger
     public SpinningSiren refSiren; //reference to the script attached to the player
     public GameObject collectible; //reference to the collectible GO
     public RepaireCollectible repColText; //reference to the script attached to the collectible
 
     void Start ()
     {
         repairText.enabled = false;
         refSiren = metaBallTrigger.GetComponent<SpinningSiren>(); //using script from the trigger GO
         repairText.text = "";
     }
     
     
     void Update ()
     {
         if (refSiren.inRepair) //if inside the collider of the collectible
         {
             repColText = refSiren.repairCollectible;
             repairText.enabled = true; //text appears
             if (!repColText.repaired) //if it is not repaired yet
             {
                 repairText.text = "In repair... " + ((int)repColText.timer).ToString(); //float timer is converted to int to display conventional 1, 2, 3, etc.
             }
             else
             {
                 repairText.text = "REPAIRED"; //if repaired, display this
             }
         }
         else //if not in repair
         {
             repairText.text = "";
             repairText.enabled = false;
         }
     }
 }

To me, it looks like some kind of memory garbage, but I have no idea. I tried to initialize the text in the beginning and set it back to "" if unused, but I am new to unity, so I don't know if I was right to do so. Has anyone seen anything like this?