Update (05AUG20): Well this camera is dead after about 3 years, my GPS was not connecting at all and so I checked the voltage to this GPS battery and it wasn't charging and so I decided to replace it again the camera worked great for a few days then I got the dreaded blue GPS light on but no response issue which signals that the NAND is bad (this has happened to be me before but I was able to fix it somehow). I wasn't able to fix it this time nor troubleshoot and so I decided to purchase a Street Guardian SG9663DR which is in transit that I hope to install once I get it.
When I first got my BlackVue DR650GW-2CH, I noticed that the date and time were not updating even after getting a GPS signal in that it wouldn't overwrite whatever the time was that it was set to. The only way to get the correct time was to do a hard format via the button on the dash cam after acquiring a GPS signal to get the correct time. It would have the correct time until it turned off and then instead of continuing with the time, it would start off from the date and time of when the camera was turned off and so my dash cam never had the correct time. It was really odd how it would not overwrite the time and save the new one once a GPS signal was acquired it seemed to be reading the time off the last file and continuing off of there instead of continuing to run.
I decided to open it up recently a to see if I needed to replace the MS621FE FL11E battery which is the RTC battery that is used to keep the time. Turns out one of the terminals on the battery was not soldered on, it was only contacting the terminal and so the connection was not good.
I soldered in the terminal and tested it out, at first it didn't seem to work, but after allowing it to charge for a while it seems to work now and the date and time of my camera is overwriting and is corrected when it acquires a GPS signal. I have a new battery just in case.
I'll write a more detailed post with some pictures of what I saw when I have time time, but if you are having these problems where the date and time is not overwriting or is always wrong, either the MS621FE FL11E battery is dead and you need to replace it or you have something similar to what I have where one side of the battery was not soldered on.