FYI - I noticed at the beginning of the game if you do NOT click to "accept" button to accept/ send the gift - the envelope (top right) will stay up there for one game - - - but if you do not use the lives (etc.) given to you, they will disappear on the PC/facebook (ugh annoying)
We have the same question here: https://care.king.com/en/candy-crush-saga/i-can-t-get-any-lives-that-friends-send-me-how-can-i-get-the-white-envelope-back#entry_65602 but the solution from King, does not work for me...
I still cannot see the friends gift / receive envelops or button. The "Score and Progression Synch" arrows cannot be used. It says "You have already synched your progress"