STEP 1 : Login to Direct Admin ( Guide here )

STEP 2 : Navigate to Email Manager -> MX Records. Click on MX Records

STEP 3 : Untick the checkbox as shown below, and click on the drop down menu for "MX TEMPLATE"

STEP 4 : Under the drop down, choose G Suite / Zoho Mail / Office365 ( Depending on which Mail Service you are using )

STEP 5 : Click on save after choosing the Mail Service you want ( The example below uses Google Suite / GSuite )

After clicking save, a succesful prompt will show, like below :

Please allow 1-48 hours for the DNS to propogate ~