I get an error when I try to add my IMAP/SMTP account

LOGS:

MAIL FROM:info@xxxxx.xxx
250 OK
RCPT TO:email@invalid.com
550-The mail server could not deliver mail to email@invalid.com. The account
550-or domain may not exist, they may be blacklisted, or missing the proper dns
550 entries.

SASL_PATH:

SMTP Last Response Code: 550
SMTP Last Response: The mail server could not deliver mail to email@invalid.com. The account
or domain may not exist, they may be blacklisted, or missing the proper dns
entries.

Duplicate, please see:

As far as I understand, it connects to the mail account and sends mail to email@invalid.com for testing purposes. The mail is going but the other party doesn’t seem to receive it. But this is just a theory. I’m not sure it’s that way.