I was having the same issue and called Garmin support. They had me sync the time with GPS and that fixed the incorrect sunrise/sundown issue.
As there are still complains about the incorrect data by some minutes or even hours, I doublechecked what my F5+ delivers. Interestingly there is a slight difference between the Garmin widget and 3rd party…
I'm having the issue that it displays sunrise as 11:31 and sunset as 1:05. Did a factory reset of the watch as well as delete and reinstall the widget. Didn't help. Tried contacting support and they ran me through the normal troubleshooting steps. Nothing worked and even after telling him I already reset the watch, he still told me to reset it again. Feel like this is a bug in the widget's software and that unless they even know it's an issue they probably won't fix it anytime soon if at all. May just delete the widget and find another one.
I'm having the same issue on my Instinct watch. Constantly displays sunset at 5:47 and sunrise at 5:42. I guess I'll call Garmin.
I am experiencing the same issue. I tried restarting the watch and I also synced the time to GPS multiple times.
I am currently in Lyon, France and according to Google the sunrise and sunset times are: 07:27 and 17:21.
According to my Fenix 5 Plus it is 10:57 and 2058. It is off by 3,5 hours give or take.
I have the latest (9.10) update installed.