Inventory System Help

Hi, I'm making a RPG-like game, and I'd like some help on what's going wrong on my inventory system. Right now, it kind of works. What I mean is sometimes it will work fine, but other times it won't at all. Basically, sometimes when I click the pickup item it registers and goes into the inventory, and it fills the spot and checks the boolean. But sometimes it requires both items in the hierarchy to be active for the boolean to be true. Here is the inventory space code:

 #pragma strict
 
 var isEmpty : boolean;
 
 var items : GameObject[];
 
 function Update () {
 
     for(var i = 0; i < items.Length; i++) {
         if(items[i].activeInHierarchy) {
             break;
             isEmpty = false;
         }
     
         else {
             isEmpty = true;
         }
         
         return;
     }
 }

And the item pickup code:

 #pragma strict
 
 var inventorySpace : InventorySpace[];
 
 var objs : GameObject[];
 
 function OnMouseDown () {
 
     for(var i = 0; i < inventorySpace.Length; i++) {
         if(inventorySpace[i].isEmpty) {
             objs[i].active = true;
             inventorySpace[i].isEmpty = false;
             break;
         }
     }
 }

Any help would be greatly appreciated!