In my normal inventory, a is a pair of pants, lowercase ell is 4 plastic bottles of water, and lowercase ell is also 5 empty plastic bottles.
When I examine a toilet, lowercase ell are the plastic bottles of water, a is the pair of pants, and now a is the 5 plastic bottles, and it won’t let me select the plastic water bottles with a or lowercase ell.
If I multidrop, hitting lowercase ell selects both kinds of bottles, the latter with a pound sign.
I didn’t try seeing what happens if I load up my inventory and hit lowercase ell (I was afraid of a crash if it tried to load up both descriptions).
I saved and quitted, loaded up my save, and now the plastic bottle is letter b and works properly for inventory and filling purposes.