I tried to get an Ol’Painful. I saw many people are having the same problem. I heard some weapons are also locked after purchase. What should I do? I want the weapon.
See this thread:
It looks like this has been a continuing issue since late August. Unfortunately, I have no information on when a fix might be forthcoming. At this point, other than filing a support ticket (which currently has a long delay) there’s not much you can do.
You could try hitting the trade forum in the relevant section, although I think the majority are currently playing BL2 rather than TPS.