We had to scan our ticket at a barrier to board a train from St Lazare to Rouen. The QR code was not accepted, a message 'Titre non valide' with a big red cross appeared. The assistant couldn't help but eventually another colleague let us through as the train was about to leave.
Are we likely to have the same problem on our return trip to Paris? Everything looked ok with our ticket, train number, date, time etc.
It's the first time we've had to go through a barrier, scanning during ticket inspection on other routes has been fine

