Here is what you should do when a user fails their survey/questionnaire.
If a user fails a survey, you can reach out to them to ensure that they didn't fail because they made a mistake on the survey but because they failed to meet the passing criteria. You can then create a case for those users under Kokomo Cases section to keep track of the failed users. If you don't see the Kokomo Cases tab under the right menu section then either you may not have the permission to create a case or your organizations has not subscribed for the Kokomo Cases services. You can reach out to your admin on how to handle such situations.
If the user failed the survey by mistake, then you can advise them to retake the survey, if your organization allows users to retake the survey, by simply going to the survey page and submit another survey. If the retake option is not available, then there is no way for Kokomo or anyone to correct the survey on user's behalf, please reach out to your admin on how your organization wants to handle such situations.