Really dumb question that I couldn't find information on. Are the doors supposed to lock from the outside using the key? I thought this would make the most sense, but mine seem to not. Not sure if the normal way is to lock manually from the inside and the outside lock is only for unlocking?

 

Should work both ways. Shoot some graphite based lubricant in there and see if it helps
Does the key turn and anything makes a sound, or just doesn't turn?