It's weekend in Germany so you might get the server on Monday, but please keep in mind that there could be a shortage of available servers and the verification of your client's account might also take a while.
You could also contact the support via mail@netcup.de
This is a customer forum where you only get answers from customers, mostly.
So unfortunately no advise from my side, but to just wait a bit.
Thank you for the answer mate. Verification was done on yester evening. I will be patient and since its a weekend my clients are also up and running about. Will check back on Monday afternoon.