Yes, you can add a response validation for the order amount or order quantity field to ensure that the form cannot be submitted if the users have not added product to the cart. Login to Neartail > click on the form to open it > Edit page will be displayed > In the Neartail Edit page, click on the order amount or order quantity field to select it > click on the gear icon for this field > Field settings page will be displayed > click Answer > click on the Configure link for the validation option > select Number, greater than, enter 0 > click Save. Please try this and confirm.