No. Reservations cannot be deleted in Bookboost, and there is no setting that changes this. They are synced from your PMS, so the PMS is where a booking is created, changed, and removed. Delete it there and Bookboost follows.
If what you actually want is for a guest to stop receiving messages, that is a different problem with a better answer, below.
Why not
Bookboost does not hold reservations of its own. It displays what your PMS pushes or pulls across, and sits on top of that data as a communication layer. Letting you delete a record here would put the two systems out of step immediately, because the next sync would bring it straight back.
So any change to a reservation, including removing it, is made in the PMS. Bookboost reflects it automatically.
If the goal is to stop messages
Deleting the booking is rarely what is needed. Three options, depending on what the guest asked for.
They want no marketing. Revoke their consent. The profile and the booking stay intact. See How to set up opt-out and unsubscribe options for guests.
They want no messages at all, for now. Add the silence tag to the guest profile. It keeps them out of campaigns without deleting or anonymising anything. See Stop a guest from receiving campaigns.
They want their data removed. Anonymise the guest profile. Their personal data is removed and the reservation record stays for reporting. See Guest anonymization in Bookboost.
What this does not do
No delete, no exception. There is no permission, plan, or support request that enables deleting a reservation in Bookboost.
Deleting in the PMS is not instant here. The removal reaches Bookboost on the next sync rather than immediately.
Anonymising is not deleting. It removes the guest's personal data. The reservation itself remains, which is deliberate, so your reporting still adds up.
What to do next
If you are unsure which of the three options fits, start with Stop a guest from receiving campaigns. It is the most reversible.
Getting help
Open Help at the bottom of the left menu and choose Talk to Us, or email support@bookboost.io.