Ok the domain names that arein mail server are:
but with this domain, the error appears:
The server ip is : 184.108.40.206
both domains (last image) have their respective A record in our dns provider, and both resolve correctly the ip server.
we tried to register that domain in another server mail in aapanel server that we have, and give the same error, both servers with aapanel in version 6.8.27