Online Booking and Online Store need a separate subscription.
If you see this message, your business needs a subscription with Store, Inventory & Orders / Appointments&Booking
Required action
For selling products buy a subscription in the Store, Inventory & Orders app
For booking services buy a subscription in the Booking & Appointments app
For quote requests buy a subscription in the Invoice Maker app
Open the respective app, go to Settings - Subscription and buy a subscription for the service you want to use.