Token bars dropping to zero automatically

I do not know what causes it. This has happened twice, under different circumstances. Yesterday I was careful to assign what each bubble and bar stood for, then saved token, THEN assigned to sheet. Tested each token to make sure a new copy appeared with a full bar. However, leaving it on the map emptied the bar to zero. I was editing a macro, saved it, and the map went black; I had to reload Roll20 webpage and reenter game. when I got in, the bars were empty. I am using the Shadowrun Advanced sheet, and the bars are set to Stun track total and Physical track totals. this only appears to affect sheets entered manually (ie, those that have the bars assigned). We have some sheets that were entered via htm file, a jury-rigged method similar to Chummer input but using HeroLab. These HeroLab sheets do not properly compute the Damage Tracks, so those boxes appear as 0. I have to leave the token bars unassigned. EDIT: Upon checking, leaving the game (I'm the GM) empties the bars. I re-entered the numbers to bring the tokens up, left the game, and they did not save.

Check the attributes tab on the affected sheets, this usually occurs when there is a duplicate attribute (with a 0 value) that the token is defaulting to (assuming the token is tied to an attribute?).

I linked the bar 1 and 2 to the damage tracks on the character sheet. I didn't understand the Attributes and Abilities tab, so left it alone

Attributes and abilities (well the attributes side anyway) is the 'storehouse' for the attributes that a character sheet displays in a pretty way. It is also where you could set manual attributes to run a game without a sheet but that is by the by. If a bar is linked to an attribute on a sheet then that attribute is likely represented in the attributes tab (there are exceptions but i won't get into them... short version is that if you  have set an attribute in a sheet then it will  be in the attributes tab). To that end I'd highly recommend looking there for a duplicate attribute that might be reseting your bar values. You can use your browsers 'find' option to ease the pain a bit ;)

ahh gotcha. I will definitely check there. thanks!