I have registered my domain incasas.com.mx in Mail Zoho.

And it is working: I can send and receive emails.

I have added users in my Control Panel and they was registered successfully.

But previously I had a user  contacto@incasas.com.mx 

When I try to add this user, only a "invitation" is sent.

Buy I can't see that invitation email in the inbox of the user.

Please help me to add that email as a user in my account  miguel.saavedra@incasas.com.mx

I can't delete and next add again, because that user is using Zoho CRM and I don't want to lose his data.

Thank you in advance