Travellers are still being overcharged for journeys despite promises an Oyster Card glitch had been fixed.
Last year it emerged some Oyster card users travelling from some stations in Redbridge were being charged Zone 1 fares for journeys on the Overground despite their journey avoiding central London.
Transport for London (TfL) was made aware of the glitch in August and told customers the problem would be fixed in September.
However, some customers are still reporting problems with card readers at Stratford station.
Anton Venter, 53, of Woodford Road, Wanstead, travels everyday between Snaresbrook Station and Ravenscourt Park in west London for work.
He changes at Stratford onto the Overground to avoid the more expensive Zone 1 fare, but was charged an extra £2.10 each time.
This problem was fixed in September, but Mr Venter claims he is now being charged £2.20 extra each time he leaves Stratford, despite buying a monthly travel card which includes Zone 3.
Mr Venter claims TfL has admitted there was a problem with some of the card readers at Stratford after previously blaming him for not touching out of the station properly.
He said he has been promised to refund each time it happens, which will take three to five working days to process.
But Mr Venter believes TfL are not doing enough to solve the problem.
He has also been in touch with London TravelWatch, an independent watchdog for London travel users, but is unhappy with its response.
He said: “The taxpayer funds a body which is supposed to represent commuters and act in their interest and deal with unresolved disputes between commuters and the rail operators.
“TravelWatch have been unable to make TfL act fairly and rectify their charging system which is faulty.
“Both TFL and TravelWatch have been aware of this for a year now.
“They are both quite spiteful in the way they talk about it and it takes ages to get through to them when I call.
“It is so inconvenient that this keeps happening. It just isn’t fair that they want you to pay out before you can claim the money back.
“People in a rush do not want to queue back up and top-up when they shouldn’t even have had to pay that money in the first place.”
The Guardian is awaiting comment from TfL and Travelwatch.