In the rule, tick the Booking types it should cover, and under Courts either keep Applies to all courts on or choose specific courts. Only bookings of those types, on those courts, count towards the allowance.
Booking limits are switched on by Nettla. Not every club has them. If you don't see Booking limits under Settings in the sidebar, your club doesn't have the feature yet. Contact Nettla to switch it on. Once it's on, you create and edit the limits yourself.
Choose booking types and courts
Go to Settings → Booking limits.
Click New booking limit, or the pencil icon on an existing rule.
Under Booking types, tick the types the rule covers: Court bookings, Matches (public and private), Activities or Private Coaching. At least one is required.
Under Courts, keep Applies to all courts on, or turn it off and tick the courts.
Click Save.
Examples
A member benefit for Court bookings and Matches, but not Private Coaching.
A padel-only cap: choose only your padel courts. Create a separate rule for your tennis courts if they need a different allowance.
Good to know
A booking on several courts counts once, as long as at least one of its courts is covered by the rule.
Company-wide rules have no court selection. Instead you choose which clubs they apply at. See "How do company-wide booking limits work?".