Strange item Purchase Problem

In the map I'm working on, a very frustrating problem has come up. This map, whenever a hero purchases an item, it gains an ability through triggers. The ability is NOT attached to the item, the hero actually has the ability.
Problem is that whenever an agility hero purchases an item, he doesnt get the ability unless he drops the item and picks it up again. On the other hand, if a strength hero purchases the item, he gets the ability instantly without a problem. I've tried to change the primary attribute of the agility heroes to str., but it doesn't do anything. Here are my triggers;

This trigger is for getting the ability when aquiring an item
Event
Unit - A unit Acquires an item
Condition
(Item-type of (Item being manipulated)) Equal to Dagger
Action
Unit - Add bash to (Hero manipulating item)
Set ABILITYGAINED[(Player number of (Owner of (Hero manipulating item)))] = bash

This trigger is for removing the ability when item is dropped
Event
Unit - A unit Loses an item
Condition
((Owner of (Hero manipulating item)) controller) Equal to User
(Item-type of (Item being manipulated)) Equal to Dagger
Action
Unit - Remove ABILITYGAINED[(Player number of (Owner of (Hero manipulating item)))] from (Hero manipulating item)

I don't think the main attribute of the hero has anything to do with this. Are you sure there isn't any other factor involved?