When you create booking sessions or pricing plans you are given the opportunity to add each to the other. Often when a client asks us to discover why their pricing plan customers can’t book onto their services with their plan we will find that the booking service hasn’t been added to the plan.
Go to pricing plans then Manage pricing plans. Select the plan you need to attached booking services or classes too. Next, check which booking services are selected. It’s likely there are some missing.
Or here's a video tutorial: