Email error: CC must be the customer's own email address or the sending staff member's own email address

When sending an email from a reservation (Reservations → open a reservation → Email), you may see this error when you try to send:

"email cc must be the customer's own email address or the sending staff member's own email address"

Why this happens

The CC field on the email dialog can only contain:

• the email address of the customer on the reservation, or
• your own email address (the one you're logged in with) — this is what the "Also CC myself" toggle adds automatically

Any other address typed into CC — a colleague, a tour operator, an event organiser, or any third party — is rejected, and the whole email fails to send.

This is a deliberate security restriction: it stops the ad-hoc email tool being used to send arbitrary emails to addresses outside the reservation. It isn't a bug, even though the error message can be surprising if you're used to CC'ing other people on booking emails.

How to fix it

1. Remove any address from the CC field that isn't the customer's own email or your own.
2. If you want a copy for yourself, use the "Also CC myself" toggle instead of typing your address manually — it adds the address for the account you're logged in with automatically.
3. If you need to notify someone else (a colleague, a supplier, an organiser) about this booking, forward the confirmation separately from your own email client rather than CC'ing them from the reservation email dialog.

Internal note (remove before publishing): flag to support for whether the "forward separately" workaround is the right advice to give, and confirm this covers cases where staff currently rely on CC'ing an owner/colleague as normal practice — may be worth surfacing to product if this is a common complaint.