Your forms library may begin to get cluttered with old forms if you constantly create new versions of your forms, or if you simply just have old forms you no longer use. Instead of separately opening every single form and deleting them one by one, you can delete multiple forms at once.
To delete multiple forms at once, simply hover your mouse over the Manage tab and click on “Forms”.
Check the box next to the forms you wish to delete and click on “Delete”. When deleting published forms, keep in mind that any data that has been submitted using those forms will be lost.