error when deleting items in some browsers

[gerzon05]

I have a problem in some browsers, when I run a function that is when I pass an item from one box to another, I need to remove two items from the box that received it.

this is the logic

when an item is added to this box it executes the function disable

I want to know if there is another way to do this execution.
I hope you can help me, thank you very much.