old boot caught fishing

seem to have a bug were when u catch the old boot when u are fishing it becomes invisible and goes into your inventory , when u look in your inventory you see no boot but form that time on nothing can be placed in the slot of the inventory because there is an item there, you can hold the curser on it say nothing you can even change items position with it in the inventory but u cannot remove it from the inventory to a crate or bin or drop it .as admin I used clear inventory to remove the problem but I have no command for the players to remove the non-item from the old boot