How to get rid of this message.

How to get rid of this message.

Hi all,

I had an @zoho.com free email addresses and signed up for the Workplace Professional Trial.  I also purchase, via zoho, a domain so I can trial out the emails.

I don't want any alias email addresses for either my own domain nor the @zoho.com domain.

When I go into Mail Accounts and click on my @zoho.com account I get the message:
@zoho.com  does not have the domain based mail alias.Create and choose a mail alias as default.

See here:
https://i.vgy.me/2iMEcK.jpg

What does this message mean and how do I get rid of it?

TIA

Greg