Ha Phi Long from the southern province of Dong Nai paid VND60,000 ($2.55) for a monthly Netflix subscription, but the very next day the access password was changed.

Long had paid the money, a third of the lowest fee that Netflix charges, to an unknown account seller after seeing an ad on Facebook. When he tried to contact the person, his calls were blocked.

"The seller might have sold this account to several users and one of them could have changed the password. Or maybe the seller changed the password himself to trick another user," Long said.

Hanoi resident Hoang Anh is another victim. He paid VND360,000 ($15.3) for a 12-month subscription, which is one-sixth of what Netflix charges, to an online seller who had a lot of positive feedback from users.

Anh transferred the money to the bank account of the seller, who had shown him his ID to establish credibility. But Anh later found out that the password he received was wrong, and the seller was unreachable.

He took to a Facebook group to report the fraud and found hundreds of others who’d been tricked the same way.

"We were able to contact the person in the ID, but it turns out this was another victim who was also tricked. The seller used his information to create a bank account under his name," Anh said.

Anh now realizes that all the positive feedback on the page was probably fake too.

Netflix was launched in Vietnam in 2016. It offers subscriptions at VND180,000-260,000 ($7.6-11) per month, which some consider high.

Netflix accounts scams have existed for years, but more fraud has been reported recently due to rising interest in the service during social distancing campaign.

Searches for the keyword "Netflix" was at an all-time high in Vietnam in the first two weeks this month when the government called on citizens to stay at home to curb the spread of the novel coronavirus, according to Google Trends.

Thanh Hai, an account seller, said that the most expensive subscription allows people to watch on five devices at the same time. But because there is a low chance that happens, sellers take advantage of the policy and sell the account to dozens of users.

Netflix has not commented or issued any warning on the dirt-cheap accounts being sold publicly in Vietnam, but starting February, it stopped the one-month free trial policy in the country.