As the coronavirus pandemic increasingly keeps children in South Korea indoors, authorities say cases have spiked of parents discovering unexpected bills for unauthorized payments.

And of the parents who had lost money, few were as shocked as a 48-year-old father in Seoul who found that a lump sum of 130 million won (US$115,000) - the money he and his wife had been saving for a new house - had vanished from their bank account in August.

It turned out their 11-year-old daughter had spent the sum while using a live-streaming app called Hakuna Live, which allows fans of streaming stars to buy gifts for them with in-app credits called "diamonds".

The girl sent 130 million won worth of diamonds to 35 streamers through the mobile payment system on her mother's smartphone between August 3 and 12.

"My wife always leaves her phone unlocked since she is visually impaired and suffers from brain damage," Kim said in an interview with local radio station CBS on Wednesday.

He reached out to all 35 streamers to ask for reimbursement. Several of them agreed to refund the money, but some 46 million won (US$40,000) will not be recovered, Kim said.

A similar incident occurred on Monday, when a middle-school student in Boryeong, South Chungcheong province, sent about 17 million won through some 60 transactions to an online streamer using her father's credit card.

Data shows that the two cases are among hundreds in which parents have received unexpected bills for unauthorized payments made by their children, as young people spend more time at home amid the coronavirus pandemic.

A total of 1,587 reports were filed regarding unauthorized online purchases made by minors between January and September this year, almost double the 813 reports made in 2019, according to the data from the Korea Content Dispute Resolution Committee (KCDRC).

However, requesting refunds or seeking legal remedies is difficult under the current law.

"In Kim's case, we see that his wife allowed their daughter to use her cellphone," said an official at the Korea Communications Commission, adding that there was no legal action that could be taken as nothing illegal took place.

Platform operators cannot force their streamers to give refunds, and card companies are not required to cancel payments made by a family member of the card holder.

"Although platform operators cannot be fully held accountable for accepting payments from minors, they cannot avoid responsibility for not having any measures such as age limits to prevent children from making huge transactions," said Hwang Yong-suk, a professor of media communications at Konkuk university.

The Korea Disease Control and Prevention Agency on Wednesday reported 118 new coronavirus cases, most of them in the densely populated Seoul metropolitan area. The national caseload is now at 26,925, including 474 deaths.

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