Problem with Facebook.

From this morning i get the annoying security check maibox everytime i post a comment(chat,personal message,comment,etc.)I searched over the internet and i saw that people solve this problem with the verification of account("add a phone")thing.However,i did the same,i veryfied my account,i received a code,i put it in and nothing.The annoying box appears every time.I tried to open Facebook with Google Chrome,Mozilla,IE and nothing happens again.I cleared the cookies and the browsing data from all of the mentioned browser and the problem stays again.I don't know what to do,i tried everything.I even changed my password and...nothing.If anyone can help me please share your thoughts.