The new barrier-free tolling system on Dublin's M50 motorway is reportedly operating incorrectly for about 10,000 vehicles a day.
Reports this morning say the system is making mistakes on around 10% of the traffic using the West-Link toll bridge.
The system is failing to read electronic tags and number plates, with some motorists wrongly receiving payment demands and fine warnings.
Motorists whose cars were not on the M50 are also reportedly receiving bills for journeys they did not make.
The National Roads Authority is continuing to insist that the system will be "the finest in the world" when it is bedded in.