On 08/20/20 parked my car around 6:00 am for my trip to Texas used my SunPass, I assumed it was working no receipt was issued. Trip back Sunday 8/23/20 around 11:00 SunPass did not work "said my TAG INVALID" SIGNAL to attendant in charge at that time, we have to reverse car and position to explain the problem. We handed our Transponder she run it, no word of what it was happening, did not say if it was working or not, handed the transported and said $79.99 short term charges. We assumed SunPass did not worked this is why we paid cash. When I updated card on Monday 8/24/00 I saw charges totaling $57.00 on dates 08/25/36/27 never used SunPass, however they claimed there was nothing they can do. I had destroyed the receipt thinking everything was ok. I was unable to produce a copy in the meantime this lady charged me twice. Want you to know what is going on with your system. I am sure you do this lots of time. Can't prove I paid but it was coincidental that I updated card and I was charged so the attendant did run the SunPass never told us but overcharged us for $79.99. Please be aware of what is going on. Sincerely, Norma Hess, Sanford, Florida