Unhappy N9005 keeps deleting KNOX

hi
I have a challenge with my N9005. It does a reboot, then when I enter the password to login it hangs for a few seconds, and reboots again. When I take take the battery out for a while I'm able to now login. but at this point it says "deleting KNOX". I realise that all my applications are nowhere to be found. Google PlayStore too is off. Bottomline is, there is nothing on the fone at this point; not even the Samsung and Google Folders. Its happend 4 times within the last month.
Please help. Thanks