official TZC pool is doing not very good now. It is not possible to login (after click to LOGIN button, there is nothing after that, login page just reaload and want to login again), and there is something with worker diff settings from the pool side (pool set much higher diff than usually). Going to other pool until everything will be fixed.
The pool operator has been working on it and looks like it's fixed.
Should be working again, as of a few minutes ago.