Everything went well until leaving when I put the ticket in to leave and it said £150 outstanding balance, I checked all my emails and I wasn’t late or booked anything wrong but it wouldn’t let us leave. We pressed the intercom and we explained to the man and he went silent and opened the barrier, he never said why it had came up with a £150 extra charge or anything just silence, if we hadn’t called we would of had to pay it so I really hope this doesn’t catch other people out and they pay that fee that didn’t need to be paid. I would like to know where the £150 came from.