Hi, Yes I did enable location. It has been working fine for months but I do find the Exercise tracking is more accurate than the "Steps" count although they are never really that far apart. This morning however, the Steps count is almost half what the walk should be. The walk was 6308 steps in Exercise -> Walking which is pretty close to the same walk yesterday.
I was thinking about it and the only change I have made to my phone since yesterday was to turn on the new Pokemon Go Adventure Sync feature (my kids love the game so I play it with them to get them out of the house). That is supposed to track your steps even when the game is closed. I checked the App Permissions for both Samsung Health and Pokemon Go and nothing stands out as incorrect. I have turned off Location in SH permissions then turned back on again in case it was affected by turning PoGo Ad Sync on. I have also turned Adventure Sync off and will test it tomorrow when I go for my next walk to see if there is some form of corrolation.
I went for my walk today with the Pokemon Go Adventure Sync turned off and Samsung Health is working again. It seems it may be that other apps which track your location may interfere.