This error usually appears when the email address entered is missing required information or contains an invalid format.
Common causes include:
The email field is left blank.
The email address is missing the @ symbol or domain.
Extra spaces have been added before or after the email address.
Invalid or unsupported characters have been entered.
How can I fix it?
Make sure the email field is completed and that the address follows a valid format, such as example@axi.com. Also, check that there are no extra spaces or invalid characters.