I use iOS7 to play clash of clans, but when I try to connect with Facebook. It disconnected and when I tried to connect it. It said that login failed, I try everything that everyone said to fixed this problem.
At last, I must delete it. But It useless. I lost all my data and can't log in.
So, Is I must report this problem to Supercell or they have a way to solve it. If you have, reply this question.
sorry man i have never had or heard of any problems with facebook login.....dont know if it was your problem or not but yesterday for a couple hours supercell had a screw up and half the continent had "login fail" for some reason.
other than that i have no idea, but contact supercell they should be more help.