I can't seem to get my array to get the combined total of a variable from a slot struct array

I have been trying to debug this func for days now and I can’t figure it out.

I am very new so I kinda hit these roadblocks often but this I can’t seem fix. This part of the BP is to get the current size of all the items currently in the player’s inventory. BP is in the image below. Please help me, I have been trying to find answer to this for while now :<. This BP currently keeps outputting 0 instead of the actual current size of the items, but oddly enough the empty slots are outputting a size of 1 instead of 0. Also the print func is failing unless my inventory is full? And If I remove the “set local variable 0” it still does the same thing.

This image below is describe how item size works. every item has a size that obstructs the players inventory space. In this image, the player is holding two items that add up to a size of 4, taking up 4 out the 8 slots in the inventory. Two item are ahead of the fella where one item is a size 3 which can be picked up while the other is 5 which cannot be picked up because the player lacks the space to fit it into inventory.

I think you’ll find it works better if you call it once, and not on tick.