Suggestion how to stop spam emails to your email account
1. You can enable SPF records (by default it has been enabled automatically)
2. You can set the spam filtering and set to high level filtering
3. You can also add the content filtering and filter your email to block emails from specific sender
4. Enable greylisting (by default it's enabled for all email accounts)
5. Don't easily post or put your full email address on any public websites such as forums or mailing list