GPS Notification Blocks Distance

It should clear once you start the activity and begin moving.

Yes.  Press start. 

I took this picture after my run. It did the same thing while running (after pressing start).

It's possible then that your FR645 lost GPS connectivity at some point during the run, and then reconnected. That would result in the pop-up reappearing. It should time out eventually. I'm not familiar with a method for clearing it manually, perhaps tapping the scroll down button?

I took this picture after my run.

Are you certain?  Your timer is displaying zeros.   If it was started you'd have some numerical figure other than zeros even if you don't have or lose your GPS signal as these data fields are independent from each other. 

Here is another picture during my run today. I don’t think my gps is losing signal because it displays the green color the entire time. It’ll disappear for a moment if I scroll through the display options, but it reappears soon after. Maybe I need to do a factory reset?

Yes, this photo clearly shows the error. Try a hard reset; if you haven't done so, before a factory reset.  Press and hold the power button for roughly 15 seconds until the watch turns off.  Restart the watch, start an activity with GPS and let it soak for about 15-20 minutes. Maybe that will correct the problem. 

Former Member

If you haven't restored the entire watch to defaults you can try just restoring the running profile to defaults. To do so press and hold the middle left button on the run profile to pull up run settings. Hit your top right button on Run Settings, then scroll down until you see restore defaults. If you select Restore Defaults from this screen it doesn't wipe the entire watch just this profile.