thank you to all for your time and advice. Finally my friend went into her Facebook security settings and found the candy crush application that she could delete from there. I do not see her account in the game anylonger. The issue is now closed.
Thanks. She actually changed her password but it did not help. Will tell her to change the username as well. It is definitely not happening from her computer.
The fact is that she says she never played the game! And she has no idea who could do that. I agree it is very strange, could this have happened if she opened her Facebook account on someone else's device? Question is any way to stop this not knowing who it is?