Hi Angelos,
The issue with not being able to finish creating profile for training support has happened a few times in the past to other people. What I recommend you do is, using a Edge or Chrome guest profile, create a new Microsoft account using a new outlook.com or gmail or live.com or hotmail.com email address, then use that account to ask your question in Certification forum.
By "guest profile" I mean when you have Chrome open on your PC, click on the little person icon in upper right corner, then click Guest. In Edge click person icon -- Other profiles -- browse as Guest. The idea is to make sure you are using 100% clean browser profile with no cookies or other existing data saved.
Even though you will use a different Microsoft account to ask your question, when a support moderator contacts you via private message you can give them the correct Microsoft account associated with your certification profile.
Please click Accept Answer if the above was useful.
Thanks.
-TP