Help needed registering an account and accessing seller central

Hello together!
For days now im trying to access the amazon seller central. Ive registered myself and completed the multifactor registration but i have never been able to log in to my seller central.

Whenever i login, i get redirected to an overview in which i have to select an account / region (all pending regestration) that does not include germany as the region where i would like to list my product.

After choosing any region the marketplace loads up but crashes with the info to retry in like 2h (this issue exists for me for 2 weeks now).

I cant contact the user support, because i need to be logged in and have to trigger the support process via the marketplace that i cant load.

Is there anyone that had a similar issue or just someone that can help me out?
I dont know what to try anymore.

Thank you very much!