Tales of airline passengers tracking their own lost bags are becoming ever more popular, as numbers of suitcases mishandled by airlines continue to spiral, and travelers invest in tracking devices.

But a passenger flying back to the airport where the tracker is showing, to collect it themselves when all official avenues fail? That's a new one.

Sandra Shuster, from Denver, took matters into her own hands when her lost bag was showing as being at Chicago O'Hare airport -- but her airline, United, was doing nothing about it.

Shuster and her 15-year-old daughter Ruby, who plays lacrosse, were flying back from Baltimore via Chicago on July 17, when their checked bag went missing.

The pair -- who'd been to Baltimore for a tournament -- had traveled with carry-on bags for their clothes, but had checked one bag containing Ruby's lacrosse kit. When they arrived at Denver after midnight, the bag wasn't on the belt. United representatives at Denver gave them a case number and told them the bag should arrive on the 8.30 a.m. flight from Chicago in just a few hours. When it didn't, Shuster called the toll-free number for lost baggage that she'd been given.

"They said, 'Your bag's going to come in later today on one of two flights.' I said 'OK, great,' but it never came. So I called later that afternoon and they said 'Your bag is still in Baltimore,'" says Shuster.

There was just one problem: she already knew it wasn't in Baltimore. Three months earlier, Shuster had bought an AirTag -- Apple's tracking devices -- to know where her daughter's bag was. "This is unique equipment, and we have to check it. Airlines are getting worse, rates of lost luggage are getting higher, and I wanted to know where it was -- so I bought the tag," she explains.

And the AirTag was showing as being at baggage reclaim at O'Hare.

"I told them I could see it at Terminal 1 baggage reclaim in Chicago, and they said 'We have no record of it.' I asked them to call Chicago, and they said 'No, we're not allowed.' They said they'd put notes in the system and the baggage team would take care of it."

When the bag still didn't arrive, and Shuster called a third time, she was told "We have no idea where it is."

They also told Shuster that she had the wrong claim number -- impossible, she thought, because she still had the sticker that had been attached to her boarding pass. The other half was on the bag.

In fact, they were right -- sort of. The claim number was indeed the same as the tag that had been attached to her bag -- but the check-in agent had attached the wrong tag. This one was for another passenger, who was traveling from Baltimore to Chicago only. That meant the bag had been taken off the plane at O'Hare and sent straight to the reclaim belt, instead of being loaded onto the Denver flight.

Turning down a 'double win'

Ruby plays goal in lacrosse, which meant there was kit totaling about $2,000 in that bag. Replacing it wasn't just about the finances, says Shuster -- a new stick needs to be restrung and then broken in, needing about a month in total. Meanwhile they were flying to San Francisco for another tournament in two days' time. Ruby borrowed some kit for that trip.

Returning from California, they stopped at the lost luggage desk in Denver with their reference number, and reiterated that the AirTag was still tracking at Chicago.

"The guy said, 'Mam, just because it's at Chicago doesn't mean it's with your bag,'" says Shuster.

After suggesting someone had stolen the bag and dumped the AirTag, she says, the United representative told her that most people immediately put in claims to replace items, get $1,000-2,000 in compensation, and then have their bag arrive in a few weeks.

But Shuster was convinced it was still there. "It had moved maybe 50 feet, and the AirTag was embedded in the bag -- I doubted someone stole it," she says. "He was implying it could be a double win but I wasn't trying to game the system -- to replace what was in that bag was much harder."

What's more, her daughter had try-outs for the lacrosse team coming up the following week.

So when she asked a Chicago friend if there was any way he could swing by the airport, and realized he was on vacation himself, Shuster took matters into her own hands and booked a flight with air miles.

A day off work and a trip to Chicago

By this time, she'd made contact with United's Twitter team, but been told they couldn't locate it. She also says she called United three times, to be told first that they weren't allowed to call through to the Chicago baggage office, then that a supervisor had authorized a call but nobody in Chicago was picking up -- and finally, again, that calling Chicago was simply not allowed.

Before booking her flights -- two hours each way, plus 30,000 air miles and around $30 in taxes -- she told United's Twitter account that she was planning the Chicago trip.

"We've let our baggage team in ORD know that you'll be arriving," they initially replied -- before half an hour later messaging again to say, "We recommend that you remain in Denver while we continue to work through our processes to bring your bag back to you."

Found in 30 seconds

By that point, Shuster didn't trust much in United's processes. "So I jumped on the plane, flew to Chicago, got to baggage claim, and it took them 30 seconds to give me my bag," she says.

"Meanwhile I'd already sent pictures of the bag, the claim ticket and its location to United. It's gobsmacking that they can't figure out how to do it better in this day and age."

Staff were holding it at O'Hare in the baggage office by the belts at Terminal 1 -- explaining the 50 feet that the AirTag showed the bag had moved.

Tagged with another passenger's details, the bag had been sent to the belt, ready for pick up at O'Hare -- and when nobody claimed it, staff had moved it to their back office.

Although multiple United staff had told Shuster that they'd updated the notes about her case, logging where the AirTag was pinging, and although their Twitter team had said they'd advise Chicago of her arrival, staff on the ground knew nothing about her case.

"They said, 'We can't believe that happened,'" she says.

"I understand outsourcing, but there are real inefficiencies here. And if someone knows where the bag is...." says Shuster, baffled that nobody realized that the passenger was actually saving them time and effort.

'We never heard of that'

Since then, Shuster -- who took a day off work to get the bag back, leaving on a 6 a.m. flight and getting home by 4 p.m. after the return flight was delayed -- has been working on getting her miles refunded.

On arrival she spoke to the baggage team at Denver. "They said, 'Wow, we never heard of that,'" she says.

They suggested she call United. As a frequent flyer, she called the priority line -- and was told to submit an online claim. Three days on, she'd heard nothing -- but less than 24 hours after CNN contacted United, the airline deposited her 30,000 miles back in her account (though not the taxes that she'd spent), along with an apology "for the inconvenience you experienced on your recent trip with United."

United said in a statement: "Unfortunately, this bag was incorrectly tagged at the start of the trip which contributed to the longer delay -- we've apologized to Ms. Shuster, reimbursed the miles used and gave her an additional travel credit to use toward a future flight. Our teams work to reconnect our customers with their baggage as quickly as possible and we regret that we could not get this bag to Denver sooner."

Shuster had not yet been informed about the travel credit at the time of writing.

'Airlines need to do better'

So what lessons have been learned? Shuster says she'll always check the claim ticket that's placed on her bag, instead of assuming that check-in staff have got it right. She'll also watch it down the conveyor belt.

Ruby is happy, and Shuster says that she herself feels "wonderful -- I've always been known for persistence."

But her main emotion is bafflement.

"What was difficult to comprehend was that it would have taken one call to Chicago to locate it, and nobody seemed able to do that. Why couldn't the guy at baggage claim in Denver call Chicago? It would have taken one minute. It was a huge hassle for me to take the day off work and use my miles [to fly there].

"And there was no apology at any point -- apart from a Twitter message saying 'we know this has been frustrating and making you anxious.'

"United seems to be very siloed. They don't have a way where these people can talked to each other and figure it out quickly.

"You can't tell me in this day and age, with all the technology available, that they can't figure this stuff out. Airlines need to do better."