Early morning commuters have been shortchanged by tens of thousands of dollars in MTR discounts because of a fault with ticketing machines. In the latest of a string of controversies since Octopus smart cards were launched last September, the Mass Transit Railway Corporation (MTRC) has admitted off-peak discounts of 30 per cent were not registered on cards at Lai King station turnstiles. The glitch was blamed on software problems with new turnstiles which failed to register the discount when a passenger entered before 6 am. The new turnstiles were commissioned last October as part of work on the Lai King station interchange with the Airport Express line. The corporation said 70 passengers a day had been affected and estimated it had gained about $30,000 in revenue as a result. An MTRC spokesman said the fault had been detected and rectified last week after passengers complained they were being overcharged. Democratic Party member Lee Wing-tat accused the corporation of attempting to conceal the fault, as it had not told passengers or the Government of the problem. A Transport Bureau spokesman said a senior official had to contact the company yesterday to seek a report. 'We spoke to them and asked them to take immediate action.' The Consumer Council said that as a public operator, the MTRC had a duty to tell passengers of the problems. 'If they made a mistake then consumers should, of course, be informed about it and the operator should consider some form of redress or refund for those affected,' council spokesman Kenneth So Wai-sang said. Asked why there had been no immediate announcement, the MTRC spokesman said: 'We admit we didn't handle the case so well. If there are any queries, passengers can contact us and we will handle the case.' The Octopus cards were touted as a hi-tech, speedy and convenient alternative to common stored value tickets, but their launch on September 1 was followed by complaints about faulty cards, out-of-service value-adding machines, concession losses, confusion over use, high costs and double deductions. Technical problems also dogged the system on buses resulting in the embarrassing arrest of a KMB passenger when computers read his card as being bogus while it was merely out of date. Commuters were angered in January when the 3.5 million stock of cards ran dry. Another 1.3 million cards were ordered but could only be delivered progressively.