As I can see from our logs, a lot of emails we sent to you in March this year have bounced back for "554 5.0.0 Service unavailable" errors. After receiving so many bounced emails, our system automatically flagged your email as invalid. Could it be possible that the email servers at @j***o.com were not up and running all time? If it helps, I can forward some of the bounced emails to you.
That said, I agree that our system should provide you a way to sort this out in case of a valid email. In fact, we will have that feature very soon.
For now, I can manually change the email address on your permies account back to the previous address, and see if our system can send emails without getting bounced. Does that sound like a good plan?