Postfix issues

I've recently changed nameserver records back to where I originally got the domain from, the only thing I use it for is mail. I have the MX/CNAME/TXT records pointing at Google for mail. The previous host I was using had an A record, but this new one does not.

My second domain+server that has Postfix/Dovecot has not been able to send to the first domain since I changed them. But everything else (Yahoo, Gmail, etc) can send to the original domain.

This is the email that I get:

This is the mail system at host mail.<domain>.

I'm sorry to have to inform you that your message could not be delivered to one or more recipients. It's attached below.

For further assistance, please send mail to postmaster.

If you do so, please include this problem report. You can delete your own text from the attached returned message.

 The mail system 

email@domain.com: Host or domain name not found. Name service error for name=<domain> type=AAAA: Host found but no data record of requested type

Here's the postfix configuration for the second domain/server.

PS, I am getting very fucked off, so I apologise in advance if I get shitty.

EDIT: The domain does not have any hosting, so I cannot give it any A/AAAA records. I have also tried this to no avail.

EDIT2: Resolved. OP didn't do things properly.