I fairly recently went to Acrobat Pro DC after using X for years. This is the first time I've tried to sign a document in DC. Did this all the time in X.
The documentation indicates that once I go to the Fill & Sign tool, I should be able to select the "Sign" icon which will provide a submenu to then proceed with importing my signature image. However, when I select the Sign icon, all I see are 4 boxes beneath it that alternate from grey to blue like it's thinking about doing something. But it never gets there. Also, in the far right window pane is the phrase "Retrieving your information...". I'm not sure what information it seems to be having trouble retrieving. I'm logged in as indicated by my name appearing in the upper right hand corner.