Hi,
Normally the “+” character is not allowed to be used in email addresses by many/most of the top email services (e.g. Gmail, Outlook, Yahoo).
For example: https://support.google.com/mail/answer/9211434
Because of this, generally, the “+” sign is used for testing purposes, so you can append some characters to your existing email address to have it act as a different address. However, because real email addresses would not contain that character, it poses no actual issue in real booking situations, in which a real customer’s email address should normally not contain this character.
What email service is the client using that allows the “+” character to be used in their address?
