Why not try to reduce the amount that you withdraw a little bit? so that, the funds for fees have more than required.
However, their telegram group exists
http://t.me/NominexExchange the support team is active at there, you can find a quick solution from him there.
I have given it another try with the same, max., amount. This time it worked. The support chat function now also functioned. This all happened after a restart of my PC. So perhaps the problem was on my side.
The Telegram support I had not been able to find because the link on the website refers to the news group on Telegram.
Summary: I am all good now with Nominex and I have deleted my warning.