theres misreads all over the place. The problem is if youre car is misread and you pay, the payment is only valid for the last journey so if you paid you might have been paying for a misread. Once you have the receipt youll be ok, even then if you cant find it, ring them, tell them. It'll be ok. As them to show you a photo of you going through the bridge at the time they say you did.
I had payments with receipt that they actually had no record of even receiving even tho I had the eflow recipt number in front of me when I was talking to the guy.