My 2016 Chevy Colorado was parked, never moved for the last month. Recently I tried to cranked it, it was dead. I needed to open a passenger door so I unlocked driver door with key, then opened the passenger door from the inside. Tried to boost the battery, now I can not start vehicle due to theft system.

Followed previous post instructions by attempting start, leave key in on position forb10 minutes, turn key off for 10 seconds, then attempt to start. Great, that worked and the truck started, theft system light turned off.

10 minutes later, I attempt to start vehicle again, truck horned twice, emergency flashers came on, wind sheild wiper came on, and the message Service Theft Deterrent System and Service Stabilitrak came on.

Now battery is dead again. WHAT IS GOING ON!?

Battery is brand new, replaced it 2 months prior to this.
VIN# is 1GCGSBEA1G1347895