If you find your Bookogs account is banned and you don't know why, it's likely that it's due to activity on your Discogs account. Please check if you have a database ban or marketplace suspension on Discogs. This may include an overdue invoice, you can check for that here.
You'll need to resolve your account issue with Discogs in order to get full usability of Bookogs once again. This could be as simple as paying an outstanding invoice, or you may need to get in touch with Discogs support team.
Once the issue is resolved with Discogs, if you still have trouble accessing Bookogs, try logging out and back in again. This will reboot your account if necessary.