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A flight attendant checks on passengers mid-flight on a Baltimore-bound flight from Hartsfield-Jackson Atlanta International Airport on April 20 in Atlanta.
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Air travel complaints surged eight times the normal amount in the past two months, as passengers complained about airline refunds during the coronavirus pandemic, according to the US Department of Transportation.

In March and April, the Department of Transportation received more than 25,000 complaints, many of which were refund-related. In an average month, the department gets 1,500 complaints.

That’s why DOT issued its second set of guidelines on Tuesday, clarifying the circumstances in which customers are entitled to refunds or travel credits.

“The Department has received an unprecedented volume of complaints from passengers and is examining this issue closely to ensure that airlines’ policies and practices conform to DOT’s refund rules,” Transportation Secretary Elaine Chao said in a release. “The Department is asking all airlines to revisit their customer service policies and ensure they are as flexible and considerate as possible to the needs of passengers who face financial hardship during this time.”

New guidelines from the department clarify that refunds should come within seven days, if the flier paid by credit card. It also clarifies that if the customer cancels and not the airline, the situation is different and the flier may not be entitled to a refund or travel credit.

“Although not required, many airlines are providing travel credits or vouchers that can be used for future travel for those passengers electing to cancel their travel due to health or safety concerns related to COVID-19,” according to the department.

In April, the department said airlines have an obligation to provide refunds to ticketed passengers when the airline cancels or significantly changes the customer’s flight, and the customer doesn’t take the alternative offered by the airline. However the terms “significant change” and “cancellation” are left to be interpreted by individual airlines.

“However, the Aviation Enforcement Office expects carriers to honor those reasonable interpretations in implementing their refund obligations and will focus its enforcement actions on instances where a carrier has disregarded the requirement to offer refunds, failed to honor its refund policies, or where it is determined that the carrier’s refund policies or practices are otherwise ‘unfair or deceptive,’” the department said.

On Tuesday, 163,205 people passed through Transportation Security Administration checkpoints at airports – 7% the number a year ago, according to the TSA. That’s up from around 100,000 in mid-April.

CORRECTION: An earlier version of this story overstated the increase in complaints in the headline and story. Air travel complaints surged eight times the normal amount in the past two months.

CNN’s Gregory Wallace, Pete Muntean contributed to this report