This is a known bug that seems to have gotten worse recently. As a workaround, whenever you drag your token to the map, immediately go into the character sheet, click on your hitpoints, then hit enter. This will force the token to the proper value. Repeat for this for AC and whatever you are using on the 3rd bar. Also, rather than dragging/dropping you could try copy/pasting tokens (after fixing them). Example: You have a group of 10 orcs, drag one, fix the HP/AC, then copy/paste that Orc 9 more times.