19-year-old Connerjack Oswalt was discovered earlier this month by Summit County Sheriff's deputies in Park City, where he was sitting outside a closed liquor store within a gas station in the dead of night ... shivering by himself and looking helpless.

As you can see, the officers approached him carefully and eventually took him to their car to warm up -- trying to figure out where his shopping cart had gone. Apparently, residents in the area had reported Oswalt before ... and he was on the Sheriff's Dept.'s radar.

The deputies scanned the guy's fingertips and that's where their search for his true identity began. Suspecting there might've been more to his story, they started running different searches ... finding that he'd run into some trouble in Nevada before landing in Utah.

They also perused missing children databases ... and before long, the Sheriff's Dept. realized he'd been reported out of Northern California dating back to 2019.

After some time, they got in touch with his parents ... and Oswalt's stepfather drove all the way down from Idaho Falls -- where the family has since moved -- to make an in-person ID ... that moment, too, was captured on police body cam. Safe to say, it's emotional.

The stepdad, Gerald Flint, has Oswalt's biological mother, Suzanne, on the phone -- and after he realizes it's their kid -- she starts to break down on the other end ... sobbing.