To change the name of a form, visit your Form Editor (if you’re in the My Forms section, select the form that you want to rename and click on the second option – Edit Form). After you’ve opened the editor, spot the form name – it is placed on top of the page, right above the fields list. Click on the form name, delete the old name, and type in the new one.
A faster way would be to go to My Forms, select the form, click on the menu icon located on the right, and select Rename. A lightbox will open where you can change the name of the form and hit Save to exit.