My hamster won't STOP chewing on the bars,help!?

I have a black bear hamster who won't stop chewing on the bars of her cage. I tried every suggestion;wooden chews,toilet paper rolls,tubes taking her out more often and Grannicks bitter apple spray. I was wondering if I am doing something wrong because I take her out an hour a day and feed her enough. Now,the hair aabove hernose is gone and there is a little red bump from gnawing so hard. I really want her to stop, but I don't know what to do! I have Habitrail Twist cage but with the adventure cage. Thank you!!!!