This happen to me twice.
The first time I assumed it was because adcenter banned me previously.
The second time, I join from new isp, different billing details, real credit card, new compupter.
This means that they banned you.
First account they already banned but when I called support, atleast they visited URL from some call center IP in usa.
The ban email looks like this, you get it only after you report issue
Based on our investigation, your account will remain closed. Please understand that we treat unauthorized account access and billing as a very serious matter and that we reviewed your case thoroughly before reaching our conclusion. We keep security checks like these in place to protect our advertisers and our customers. For privacy and security reasons, we cannot provide details around your specific account closure, but the most common reasons we are forced to close Microsoft Advertising adCenter accounts include:
The payment method on file was not authorized by the account owner
The account was accessed without authorization
The account is related to an account that was previously closed
The account was determined to be high risk to other customers or advertisers, as stated in our Editorial Guidelines