How to unlink Facebook from Twitter?

I can´t stop my twits from posting automatically on my Facebook account ! When I try to unlink the apps directly from twitter this message shows up. "Facebook reported an error. The error has been reported to our engineering team. Please try again, because it could be a temporary problem." I deleted the Facebook app on twitter and de twitter app on Facebook, but still de twits appear on ma Facebook account. I cant use my twitter account because everything appears on Facebook. What can I do?