Have strange forward to non existing emails of the old domain

[Vladimir]

The correct email still receives the mail but also receives the mail for mail delivery failure which is kinda annoying. There are no forwards and I can't figure out why is this happening.

In this example, marketing@bgm-online.com doesn't exist.

[NCKNE]

@Vladimir You might want to check (via command line) if you have any stale sieve filters left for the mailbox. This might happen if you switched the webmail installation.

[Vladimir]

How can I check this? Is it possible to give me the commands?

[girish]

@Vladimir Can you check /home/yellowtent/boxdata/mail/vmail on the server? There is a directory for each mailbox. If you enter the mailbox, there is a sieve directory. You can just delete the entire directory to remove the rules and then restart the mail server, in case dovecot had cached it.

(You can also do a quick grep on the address in the above directory to see if it's referenced anywhere else).