Heres the way it works, when you pay for a trip with Visa or laser online or at a pay point online, the payment is for the last trip prior to the payment. That info courtesy of their cust service.
However, if theyve tracked a false transaction (ie, a toll visit) in the meantime then thats what the payment is against and you get 40e bill in the door. I opened an account and via the online tracking system caught 4 trips that I hadnt made compared to 20 I had (20% error rate, nice), I asked them to provide photo evidence to me that I made those trips or else I wasnt paying, so eventually (after phone calls, no reply via mail) got the trips refunded. they should have photo evidence of every trip.
Also, if you pay in a shop then some of the payments arent going through even if you get a receipt which screws up the payments even more. lots of evidence of that happening from reports on here.
Ive more as well but grrrrrr.... rant over for now.