Can't open door when something is in off hand and crouching.

So what happened was we had slabs in front of the doors so mobs didn't get in, I had something in my off-hand and I crouched and tried opening the door but it wouldn't open so I took the item out and I could open it, so I tried other things like food, usable items, and blocks though EVERYTHING didn't open the door while in my off-hand, even my friends had the same problem so... Can you fix this?