Encryption: How to decrypt a form

How do I unencrypt form?

In order to decrypt a form you will need to upload your private key. This key would have been generated when you encrypted your form. 

Usually the key is called "jotform.key" and can be found in your Downloads folder.

If you cannot find your private key it is impossible to decrypt your data. And you should disable encryption for your form. This will prevent new submissions from being encrypted. So you will be able to access new submissions. However, you will not be able to access the old encrypted submissions.

Please read this guide:
Encrypted-Forms-and-How-to-Use-Them