No fill & sign tool and signature button not working

So as per the title, when I open an PDF in Acrobat I don't have a 'Fill & Sign' tool available under the tools section or in the right hand tools panel. Additionally the 'Sign document' button in the top tool bar is none functional. I have uninstalled and reinstalled Acrobat twice to try and resolve this.

This is basically the only reason I use Acrobat. How can I get support on this? I can't seem to figure out how to contact Adobe support...