Facebook login problems

Have you tried to hard reset the device? To do this just press and hold the power and home button and the same time until you see the screen go black and the apple logo appear , now let go of both buttons, allow the tablet to start up. Try the facebook app again, does the problem persist? If the problem still persists, check to see how much space you have on the tablet, sometimes the limited amount of space on the device can prevent an app from functioning correctly. If you find there is not very much space remove several items, to create more storage space, then attempt to use the Facebook app again, does the problem still persist? If so, check the App Store to see if there is an update for the facebook app, if you find one under updates, install it, try to run the App again. I hope something here has helped you resolve your issue.