Why is it actually not possible to search specifically for customers who have not yet made an appointment via a specific booking type z.B. Have you booked the web?

Currently, only the following is possible:

Filter option: transaction type

(Reach out to customers based on their previous booking types)

Customers who have booked an appointment via [web, Android, iOS, third-party API...]

Desirable:

Customers who did NOT book an appointment via [web, Android, iOS, third-party API...]