You should be able to turn it off by using the key and locking then wait a few seconds then unlocking the drivers door, if that doesn't work then do the same to the passenger side. If the system is still in lock down then it will have to go to the dealer and have the system reflashed. A lot of late model vehicles require a special tool that plugs into the lighter or power port before the battery is disconnected, this maintains the presets in the control systems thus eliminating problems like this. I bought one just in case.
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