i think no one can fix this issue but NOKIA or FACEBOOK bc the problem come from when you share something from any ovi app widget to facebook, even the upload complete but it doesnt go through in fact and then after that, your facebook chat account get stuck in account is in use.
You guys can make a new facebook account, then try to login with your nokia n9, it will work. Then go offline, then try to share something from an ovi app widget. After that, try to get online again, you will get account is in use.