Unable to create a new electronic signature in Preview

I am trying to add a signature to the _Preview_ using ***Tools > Annotate > Signature > Manage Signatures*** I then click on _Create Signature_ Note that I need to use a camera-ready _picture_ of a handwritten signature - (not mouse created). So in the dialog I choose "Camera", then put the page with signature in front of the camera and click _Done_ But then the "new" signature is not created: the same single entry is still there (which I did years ago in a much older version of _macOS_). Why is a new signature not being created? I am on _Big Sur_. **Update** Here is what is in my _Keychain Access_