I think its impossible to get a  9 digit as private keys and i think you are holding only encrypted code you need to find a way tools that can decrypte that can help.. Or maybe you are using some encoder before and you just didn't remember it yet?
You can try this link and decode your 9 digit and maybe you can find here the solution https://codebeautify.org/base64-decode
You may also try also the other tools there to decode or decrypt your 9 digit and maybe you can remember that you just encode your private keys or seeds that turn into 9 digit..