Hello and thanks for reaching out!
You can try getting your device quickly reflashed at a ATT Device Support Center (not an att retail store). That might revert your OS. You can also have your device reflashed by us, however, you will need to send in your device.
If you need additional assistance please contact us again. You can also reach out to us via twitter or facebook for quicker responses.
Thank you and have a great day!
Samsung Mobile Support is now available on Twitter & Facebook!
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