How to revert if I accidentally deleted a section of my form?

can  you undo an action when you are building your form. I somehow accidently just deleted a whole long text section of my form, it has tables that I created in there and I do not know how to get it back 

Please help

Yes, you can do this by reverting to your previous version of the form from the revision history option of your form.

1. Go to your My Form page, select your form and select "Revision history" from under the More option as shown below.

2. You can review the revisions made to your form in the subsequent window. Select the version and hit on "Revert to this version".

Detailed steps for this are mentioned here: How-to-View-Form-Revision-History

Do try this option and let us know if you are still facing any difficulties.