Thanks to the merger with Continental, United Airlines is now the nation’s largest commercial carrier, but has the airline been able to keep up with its increased customer base? On Friday, the Dept. of Transportation fined United $350,000 because it failed to provide prompt refunds to thousands of customers in 2012.

Additionally, DOT said that United filed inaccurate information about mishandled baggage, overbooked flights, and incidents involving animals.

According to DOT, in the three month period from March 2012 to May 2012, United failed to process passenger refund requests in a timely manner. Federal requirements state that, for credit card customers, airlines must process refunds within seven days of receiving a completed request. For passengers who paid by cash or check, airlines have 20 days to process the refunds.

“When passengers are owed a refund, they have the right to expect the airline to act promptly and give them their money back,” said U.S. Transportation Secretary Anthony Foxx. “We also expect airlines to file accurate and timely consumer reports so that passengers will have the information they need when choosing an airline.”

The second half of that statement refers to the revelation that, between January and October of 2011, United was underreporting incident numbers to DOT on mishandled baggage reports and bumped passengers. In 2012 and 2013, United failed to file timely reports on incidents involving the death, injury, or loss of animals on the airline’s flights. These failed filings meant that regulators and consumers received an inaccurate picture of the airline’s quality of service. However, because the airline disclosed these reporting errors to DOT, the agency did not assess a fine for these violations.

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