EMail to "Members@..." not working

I sent an email to "Members@DartBankToastmasters.com" and nobody received it.
I set myself up as Vice President of Public Relations and sent an email to VPPR@DartBankToastmasters.com and got a message "unable to deliver message after multiple retries, giving up".
I attached some JPGs: the DNS with GoDaddy, email setup in the administrator console in www.DartBankToastmasters.com , and my email error message.

We're a new club with a new club web site. The email hasn't worked in the two weeks that we've been up. It's not like it worked and then broke. 

Change your MX record name to mail.domain.ext. It's been a few years but I think I recall having this same issue and changing my MX record to get my custom domain email forwarding to work.

Ref my club's GoDaddy DNS config;



 

Yes. My "MX" record name already is " www.dartbanktoastmasters.com .". The "Data" already is "mail.dartbanktoastmasters.com."
I feel like I already set it up according to what you said in your response. 
I checked again and again for a spelling error. It looks right.

Do you have another recommendation? 

Please follow the instructions here:   support.toastmastersclubs.org/doc/item/dns-settings-overview
Your primary A record and your MX record look good
You need another 2 "A" records for mail and www