Missing hiker ignored calls from rescuers because...
It was an Unknown Number.

(CNN) — A Colorado rescue team has some simple advice for lost hikers or anyone else who might find themselves stranded in the mountains -- answer your phone.
Lake County Search and Rescue says it got a report last week that a hiker hadn't returned from a hike on Mount Elbert. The hiker had set out at 9 a.m. on October 18 and wasn't back at 8 p.m., LCSAR said in a post on its Facebook page.
Rescuers tried to call the person's cell phone multiple times, but weren't able to reach them.
Five LCSAR team members looked for the hiker in areas where people tend to get lost, but called off the search at 3 a.m. A three-person search team checked another area at 7 a.m.
They got a call at about 9:30 a.m. that the hiker, who was not identified, had returned to where they were staying.
The hiker had no idea that rescuers were looking for them, the post said.

One notable take-away is that the subject ignored repeated phone calls from us because they didn't recognize the number,"