Hello,

I don't find database linked to your current email.

So, what you can do, is send an email to online@odoo.com to ask to unlink the old database from your contract. (need your contract id)

Before to do it, don't forget to drop your test database, else Odoo will continue to receive warning for duplicate...

If you really want to keep the test db simultaneously, you need to duplicate it with the checkbox "Generate a new database uuid' unchecked !