Changed firms, and old firm locked my clients out of their online statements

So I left UBS for a new firm, and most of my clients, thankfully, tell me they're sticking with me. All many of them need to do is print out a UBS statement 

and file it with the paperwork to transfer to the new place. OK so they're going online and...UBS has locked them out! Many of them are finding "no account

available" and custserv says it's because they're in transition. What the )!#&!_)&$? Anyone had this happen?