Discrepancies between supercharger clock and car clock

[Long Range 3]

Hi all, want to see if any of you have noticed time difference between supercharger clock time and the car's time. I was at Atascadero, CA supercharger yesterday evening and plugged in when the car's clock displayed 7:02pm which is after the free charging session started. I came back after charging for 20 mins and continued on my journey, only to find that the supercharger stamped my start time as 6:59pm and I was billed for the entire charging session. I contacted customer service and they noted this could be an equipment maintenance issue and that the superchargers have a different clock/time than the car's time and/or real time, but they would not offer a credit unless i can have a picture to show the time difference which I do not know how to obtain as I do not have the supercharger time and didn't even know the charging session is not based on the car's time. I just want to see if anyone had experienced this issue before.