As Malaysians brace for the good and services tax this Wednesday, AirAsia passengers may want to check their receipts to see if they received an early edition.

One passenger who booked a flight on March 26 found that she was charged GST on her booking fee, for the April 3 flight.

However, passenger PinPing Tan said the AirAsia officer who dealt with her complaint claims hers is an "isolated case" due to a "system fault".

"So far I am the only case they are aware of, so no idea how many tickets were charged," she wrote on Facebook.

Tan also uploaded her receipt which showed that she was charged 24 sen in GST, levied on the direct debit processing fee of RM4.00.

AirAsia promised they will refund the GST mistakenly charged, she said.

"Those affected, please alert AirAsia. They want to hear from you," she said.

When contacted, AirAsia said Tan was caught in system tests done in preparation for the GST.

"The guest mentioned in the query has coincidentally entered into the test window, resulting in the 6 percent GST being reflected in the guest’s payment.

"This isolated case was immediately brought to AirAsia’s attention and the matter has been resolved on March 27, 2015 directly with the guest," it said in an email to Malaysiakini . 

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