My key was stuck as well. This guy shows the easy way to change the ignition switch so it shows the connector.
To reseat, pull the connector out and put it back in and make sure it's connected, snapped and secured into the switch. If that's not the problem then maybe your ignition switch is junk. I replaced mine for like $15.
Dorman 924-715 Ignition Switch...
https://www.amazon.com/dp/B00GJ1JC08/?tag=gmtnation-20
It freaked me out but's not a hard project. Hope this helps.
Fyi, the owner before me stripped out the negative battery terminal. Had to replace the battery at the same time. If positive and negative terminals are removed which resets system, you'll likely need to do a HVAC reset. That is, my vents air was blowing different and ac didn't work.
Recalibrating your Chevy Trailblazer’s HVAC system may be all it needs to correct A/C malfunctions, but the process of resetting it can vary by model year.
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