I've been experiencing this for the past 2 days and honestly, it's really annoying now.

Certain interactions with Storage Containers (of any kind) and specific stackable items will not work.

You cannot split the stack, nor transfer it completely to another storage area.

The button allocated to the Accept function does not activate the storage transfer, leaving you with the only option, to exit the storage container:

This is getting frustrating because I have found caches of weapons, but I think it is completely unneccesary for me to carry 14 or 6 of the same kind of gun around personally.

Especially with the weight limit imposed.

It even causes problems with the Vendors, I cannot purchase Ammo from them either.

If it keeps up at this rate, I will soon be at the point where I have to stop playing because my Inventory will be 99% full of useful weapons, but I won't be able to transfer them in a storage container.

Edit: Through much trial and error. I figured out the problem.

The button to transfer multiple items is Enter, not E.

The UI interface was telling me to use a button that does nothing!