When you pass through a free-flow toll (péage en flux libre) gateway, your number plate is recognised by the free-flow toll system. If you have subscribed for the license plate subscription, you pay automatically for your free-flow trips. Thus, you will not see them on the aliae.com payment site because they have been already paid. 

If you have an electronic toll tag and you use the A79, the gateways detect your tag when you travel on the motorway. 

All electronic toll tags are recognised by the free-flow toll (péage en flux libre) system, even if you have subscribed to an offer with another provider. Your trips are then paid automatically each time you travel, like on any motoway!