Thank you, @bekicrusher and @kiara_wael I restarted and reinstalled both Facebook and Candy Crush, but the thing that fixed it for me was when I was signing in to 2 accounts alternately after clearing data each time! My levels are finally back 😭 thank you so much for the swift replies!!!
I just experienced the same issue and I was on 2100+ level :( I uninstalled Facebook, cleared cache and re logged in and I'm still at level 1. I'm a little bit heartbroken losing my progress. :( This was taken Oct. 1 this year. The last screenshot I took but not the last level I played in. :(