How to recover a deleted submission?

How do i recover a deleted submission that has not been downloaded?

There is no option to recover deleted submission data in the submission data panel. What you can try is the  Revision History tool and revert your form to a previously saved point. It will restore the previous submission data as well.

Another way to regain the submission data is via the submission email. You can review the submission sent email of your form in your sent email history logs.