Level 4 and 5 team members can delete a form, but only if all submissions to that form have been deleted first. To delete submissions, please follow the directions in this help article.
Once all submissions have been deleted from a form, hover over the form's title in the Forms page and you will see a trash can icon appear on the right. Click the trash can icon to delete the form.
Additional questions? You can also contact support directly by filling out the form here.