AirAsia is offering refunds to thousands of customers affected by charges incorrectly levied on young children over a seven-year period. In what appears to have been an administrative error, the carrier imposed Australia’s $60 passenger movement charge (PMC) on children under 12 years old on certain flights from Darwin to Bali between December, 2010, and September, 2017. This was despite the fact children that young are exempt from the charge and the airline did not levy it on children taking other flights from Australia. The airline has since apologised for the mistake, believed to have affected about 10,000 customers. Australia’s competition watchdog stepped in after media reports in September quoting passengers whose children had been subject to the charge. “Some AirAsia customers have been incorrectly charged for a levy of up to $60 that did not apply. Affected customers should contact AirAsia to obtain a refund for that charge,” Australian Competition and Consumer Commission deputy chair Michael Schaper said in a statement. “AirAsia has acted quickly to address the error and has committed to providing refunds within 21 days of receiving supporting documentation from affected customers. The ACCC will monitor the refund process.’’ The ACCC said AirAsia should have emailed affected customers last week and urged any affected customers who had not received a notification to contact the airline directly. Meanwhile, the budget carrier’s Singapore operations will relocate Tuesday from Changi Airport’s Terminal 1 to Terminal 4. All AirAsia flights scheduled for that day will arrive at and depart from Terminal 4 according to normal schedules. AirAsia Singapore chief executive Logan Velaitham said the move to Terminal 4 was  in line with AirAsia’s vision of becoming a digital airline. “This year, the focus in Singapore is to embrace Fast and Seamless Travel (FAST),’’ Velaitham said. “We collaborated with Changi Airport Group (CAG) to automate and innovate our check-in and airport experience. “When you fly out of Changi with us, expect a fully automated service with FAST from door to gate, which integrates seamlessly into our own innovations on mobile and web.” The airline will deploy 19 check-in kiosks, 14 auto bag drop machines, two document check counters and two payment counters at row four, with group check-in services available at row five. It said passengers would be able to check-in at home via web and mobile, print their bag tags at self-service kiosks and drop their bags at the auto bag drop machines or proceed directly to the gate if they had no check-in baggage.