Hi, I am A. Stevens here to help with your question!
I think the next thing to do would be to perform a factory reset of the Galaxy Tab.
Before you do that, make sure you have backed up your device.
If you continue to have issues after the reset, your hardware is more than likely faulty.
Samsung will repair it or replace it if you are within warranty.
From a home screen, select Apps Apps icon.Note Located at the bottom when viewed in portrait or at the right in landscape.From the Apps tab, select Settings.Select Back up and reset.Select Factory data reset.To reset the device select Reset device.If presented, enter password/PIN then select Continue.Select Delete all.Perform Initial Activation and Setup.
If you have an SD card in the tab i would take that out before resetting.
I've heard of people getting their SD card erased even though it should not have been.
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