Half of all ticket machines on station platforms do not recognise the note, which was released into circulation by Germany's central bank on May 1st, wrote the Süddeutsche Zeitung on Wednesday.
Around 3,500 machines are believed to be affected by a software failure which means they cannot recognise the new, more secure and more colourful notes. Instead, they simply spit them back at would-be passengers.
“The appropriate software update was delivered too late and with defects to one of the two ticket machine manufacturers,” Deutsche Bahn spokesman Andreas Fuhrmann told the paper.
All the machines should be updated by the end of the month, said Fuhrmann adding that passengers who cannot buy a ticket because they only have the new note should pay their fare on the train.
Anyone caught travelling on an S-Bahn without a ticket and can plausibly prove that it was because of a defect machine not accepting their money will only have to pay the cost of the fare, rather than the full fine.