Storyline not opening - keeps asking for sign in

I paid my sub for Articulate 360 and installed Storyline.

Have been working on a Storyline project for about 10 days.  Suddenly I can't open the project.  The software is locked on a screen with option to sign in or exit.  Signing in to Articulate 360 doesn't do anything, and I can't install SL as it's already installed.  Exit is the only option.  So back to where I began.  Can't open the project.

Indeed, can't work with SL at all.