SAN JOSE, Calif. (KGO) -- A San Jose family that's been going to Vietnam for decades thought they knew how to avoid roaming and internet charges. They already knew traveling overseas can result in exorbitant fees on your smartphone. That's why they were really stunned to get a bill for more than $13,000, and ended up reaching out to 7 On Your Side to get the whole issue settled.
"It's like whoa, what's going on?" said Vivian Chung, while still reeling from the shock.
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She and her children had just returned from an annual family reunion in Vietnam, where relatives from many countries gathered on an island off the southern coast. While there, they celebrated her mother's 84th birthday and frolicked on the white sand beaches. The family returned home to San Jose, brimming with good spirits, until the jarring discovery sent them crashing down to earth.
"We know we cannot use the phone and it's always on airplane mode," Chung said. "How could this happen?"
T-Mobile charged Chung $13,470 for internet access on her son's iPhone. The charges were all reportedly incurred by Nicholas in a very short period of time while they were flying over Vietnam. Chung estimates they racked up the charge in just one half-hour.
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"How can this phone bill (be) like $13,740.19 in one half-hour?" Chung asked. "Oh my god, we almost fainted. I said, 'This costs more than the trip.'"
Nicholas got in lots of trouble with his parents, even though he insisted he never used the internet on his phone.
"I was confused and scared,'' he said. "Because $13,000 is a lot of money."
Nicholas said he switched his phone into airplane mode for the entire trip just to avoid these kinds of charges.
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"I know for a fact when you're on airplane mode you cannot have internet access,'' he said.
And that is true.
He does admit he was playing games on his phone during the flight, but only offline games that do not need internet to play.
"I started a new game. You can see it does't require any internet at all,'' Nicholas said while demonstrating how he turned off his iPhone internet and stayed in the same mobile chess game he played on the plane. It kept him busy for the entire flight without a data connection.
So, why the big charges?
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Chung called T-Mobile right away. They said Nicholas must have downloaded a movie, music or something else.
He didn't. So T-Mobile agreed to reduce the bill to about $3,800. Still, the family thought any charges were unfair.
"We didn't want to pay for something we didn't use,'' Chung said. "We didn't know where to go, but we watch Channel 7 news every night and I know about Michael (Finney). So we decided to call because we really needed your help."
After she contacted 7 On Your Side, our team reached out to T-Mobile and asked how the phone could rack up internet fees when it was on airplane mode. The company didn't provide an explanation except to say that Vietnam was not included in the T-Mobile free roaming plan, though it is now.
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The good news for the Chung family is that after ABC7 contacted T-Mobile, the company agreed to cancel out the remaining charges on the bill. In a statement they said:
"Customers on T-Mobile ONE or Simple Choice North America plans have unlimited text and data - as well as low rate calling - in more than 210 countries and destinations around the world with Simple Global. However, T-Mobile recommends, before a trip, customers who are traveling internationally either call Customer Care, or check international roaming coverage and rates online."
Chung was ecstatic.
"We were just like, yes! Wow, 7 on Your Side!" she said. "I was so glad you are here to help all of us, a lot of people like me. And really, really thank you so much."
So, how can you stop apps from using data in the background? With an iPhone, go to settings, then look under Cellular Data, and switch the data use to the OFF position. It's similar for Android phones. Go to settings, find the app that may be using data in the background, and tap it to enable "restrict background data."
Here's how to fix your phone so you don't end up getting charged!
For more stories, photos, and video from 7 on Your Side and Michael Finney, visit this page.