With form validation, Whatfix ensures that user input is validated against criteria and if the input is not found compliant, then an error message is displayed. For example, if there is an incorrect entry on a form that is being validated, and the user tries to submit the form, then the user is displayed a warning. If there's a step that is particularly important to complete correctly, when there is a failure, the branch feature can be used to redirect the user to the failed step 3 by showing the flow popup again.
Include the following snippet in your integration script section after adding the flow_id and the desired step number. The flow ID for a walkthrough can be seen when you navigate to a particular walkthrough on your dashboard. It is the alpha-numeric part at the end of the URL