Can't add jpg signature to PDFs on new laptop

I purchased a new Lenovo laptop, installed my Creative Cloud applications, and now discover that the "FILL & SIGN" tool is not present and I cannot click on the Signature tool icon in the program to add a JPG signature to documents.  This is a critical problem for me and I need the solution. 

I have gone into the PREFERENCES>SIGNATURES and unchecked "Use modern user interface . . ." and rebooted the program -- doesn't do anything different.  I can point to the Signature tool and the "Sign document by typing or drawing a signature" message appears, but nothing happens when I click on the tool.  

There is no FILL & SIGN tool in the MORE TOOLS panel.  I am at wits end.