Why can't I decrypt my submission data?

I unlocked the form but all I see is random letters and numbers in my submissions

I have checked the form you kindly provided and found that you have two encrypted submissions, and I was correctly prompted to enter the private key to decrypt them.

Please note that you are still enabling form encryption, which means any future submissions would also be encrypted:

For more information on encrypted forms and how to use them, please see our guide here: https://www.jotform.com/help/344-Encrypted-Forms-and-How-to-Use-Them

I hope this helps. If you need further assistance please let us know. Thank you.

correct however when I put in the encryption key I still only get random letters.
Sent from my Sprint Samsung Galaxy Note5.
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when I put in the encryption key I still only get random letters

This could only mean 3 things:

1. You're using the incorrect key

(SOLUTION: Use the correct one you generated and downloaded the moment you enabled Form Encryption)

2. Your browser has a saved key (the incorrect one) on its local storage

(SOLUTION: Clearing your browser's cache and cookies then viewing your Submissions Page will prompt you to use a key to decrypt. This time, please ensure you will use the correct one)

3. There's a step you're missing when decrypting your data.

To give you an idea how to decrypt your submission data, both from your Submissions page and from Email, refer to the following clips:

1. Via Submission page:

2. Via email notification:

Once again, ensure you are using the correct key for the encrypted form you're trying to decrypt. There should be no problem if you're using the correct one as shown on the examples above. Keep in mind that if you lost your Private Key, sadly, there's nothing much we can do. This is something that we mentioned on our guide for Encrypted-Forms-and-How-to-Use-Them 

(an excerpt from that page)

What happens with submissions if we lose the private key?

If you have lost the private key, then there is not much that you can do - it means that your encrypted data is lost forever, there is no copy of the same on our servers and it is not possible to crack the one that you had.

 

The only recommendation is to turn off encryption right away on each form so that you can start receiving the submissions - which you will be able to see (as the encryption is turned off), while you can leave the encrypted submissions in your Submissions Panel in case you find the key at some later point in time.

If by any chance you lost the key, don't know where it is anymore, where it was saved, etc., then there's no chance of decrypting existing encrypted submissions anymore. I would advise you to disable encryption now so you won't need to decrypt future submissions.

IMHO, Form Enryption is not necessary since the forms and submissions are already secured by default. This is only needed if you're collecting really sensitive information and from how I see your form (62236985808165) you're only collecting regular details.