Issue: The administrator of WHMCS clients has changed the email address of a client profile, and the email address is known to be valid. There is no feature in the front-end application to toggle on the “verified” status.
Solution: Access the database using phpMyAdmin (for example) and update the client information.
Find this table: tblclients and search the table for the client you wish to update. Access the client record and search for the field: email_verified
In the email_verified field, change the value from “0” (which means unverified ) to “1” (which means verified).
Save the updated changes and the email address will appear as verified in the front end.