This selection is only available if you're using our most recent version of the Online Scheduler (Version 3)
Navigate to Settings -- Office Settings -- Online Scheduler Settings -- Online Scheduler V3 Settings
Then, scroll down to the second half of the Settings section to find the Require select at least one primary service before adding any ancillary services to the cart widget. Click the widget located to the far left to shift the toggle to the right to turn it green and activate the feature.
If you have any questions, please feel free to give us a call at (800) 700-8112, or you can email us at email@example.com or open a chat in the upper right corner of your ISN!