Follow the below steps To Avoid Spam Mails

You have two options to avoid spam,

1. To prevent forged mails, you can create SPF record for the domain. If you want us to create, please let us know.

2. To make your spam control strict, please start using mail filter in the cpanel and change the spam assassin score to the lower value. But not less than 3 as the spam assassin will become stricter.