How to go about updating slots for a MP Inventory

So i am making a multiplayer inventory system and everything is working fine but i just cant get my head around how to update a slot i have the current thing set up

So, UpdateSlotAtIndex function is in the Inventory Component that is attached to a player and is basically using the UpdateSlot event in the SlotPanel widget which is basically my widget for a slot in the inventory now i thought this would work but i always get acessed none errors in single player and in multiplayer while testing and of course it doesnt work:

Multiplayer :

Singleplayer (pretty much the same thing) :

To further explain i am getting the Slot Panel Widgets from my Inventory Panel like so:

And i get the Inventory Panel from my Main Panel which has the Inventory Refrence inside it and i am getting the Main Panel refrence inside the inventory component like this :

If you know any other idea how you would do this or how do i improve my already existing take at it to work please let me know thanks in advance

PS. If you need any more screenshots let me know i will give you them in the comments along with the additional info

Thanks in advance!