Remove Item function not working

Hi, all!

Running into a bit of a problem on the 2020.1 version making a 1.12.2 mod. I'm trying to have steak removed from the player's inventory if it's in their hand when they right click a mob, but there's some really bizarre stuff happening in-game. The game will remove the steak as normal at first but if I throw a steak or attempt to move it in my inventory the removed items immediately return. I've attached a screenshot of my block code for reference...this is driving me nuts. If this is a bug in MCreator itself, is there anything I can do to work around it?

Thanks!