Contact Form Submissions don't go through!

Hello,

I have a form setup with simple text fields and a file submission field. However, whenever someone tries to fill out the form and clicks submit, they get the following error:

Error saving data! Please try again.

Error debug information: Column ‘notifyto’ cannot be null

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This is only happening on this one form and other forms seem to be fine. I’m not sure if I have something set up incorrectly in the settings. I have the paid version of the plugin so I do have full functionality. The form was working previously and now it stopped working with the error above.

Any ideas what might by wrong?

Thank you!

https://www.ads-software.com/plugins/cp-contact-form-with-paypal/