Hi, I have very recently purchased forerunner 645 music. I love it but I’m having problems that the elevation it’s recorded is vastly over what I know I’ve done.. on a run during the week it recorded a 1800ft elevation gain, I know from doing this run many times before with my old Polar watch that the figure was more like 500ft and after doing the ‘elevation correction’ on Garmin Connect it did adjust it down to 504ft. How do I get this to be correct for future runs without having to manually correct every time?