How do I revert my form back to a previous version?

I've tried to use the revert feature after several hours of work mysteriously disappeared. There is no history available for about an hour today, immediately before the work disappeared. How can I retrieve my work QUICKLY.

All the changes should be reflected on the revision history tool of your form, please check the history on the two different methods, from my forms page and from the builder directly, as described on this guide: https://www.jotform.com/help/294-How-to-View-Form-Revision-History 

If the problem  persists, please provide us the details about the changes you have done and the form's link as well. 

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