I want to make an attribute system, but I can't add special items

btw, everything you read next was translated using google translator(and my additional), and I also want to note that I am not professional in mcreator, so yes :)

what I need to do, I'm making a mod for my map, and there's a semi-RPG system with attributes of strength, agility, intelligence. I need to add items that will give attributes, that is. item for strength - which gives strength etc. I need to check for the presence of a certain item in the player's inventory, and if this item is there, then add (conditionally) 1 to the attribute (conditionally) strength. In mcreator there is a check "when item in inventory tick", but i cant use it, because the attribute will be given infinitely. 

Do you have any ideas how to make this work?
I mean to make the "when in inventory tick" run once, or do something else altogether? i just need to add (conditionally) +1 to the attribute while the item is in the inventory.

there is how my mod works:


and something like this:




I also want to add that I am hyper sleepy now, and in general I thought that this part of the mod would be the simplest, but for some reason I have been sitting for the hundredth hour not understanding how to do this simple thing