Why am I asked for a private key to view the submissions?

I'm being asked for my Private Key Wizard in order to view my form submissions. What is that?

I see that you have enabled the form encryption for your form and so it is asking to upload the private key.

When the form is enabled with encryption, you'ld be prompted with a wizard to create and download the private key which is now required to view the submissions. Please check the downloads folder if you have the key. Please refer to the guide below for more information on form encryption.

https://www.jotform.com/help/344-Encrypted-Forms-and-How-to-Use-Them

Hope this information helps! Please get back to us if you need any further assistance. We will be happy to help. 

Can you tell me the date I created this form? I cannot find the download of the private key; perhaps the date will help. Or is there another way to do this? I use a Mac. 

The filename for the key by default is jotform.key

It should be possible to search for the file by name:

https://www.macworld.co.uk/how-to/mac/how-find-lost-mac-os-x-files-3613260/