Card with states stoped coloring

I created a dashboard with card states. Based on a value, I color the letter of my card. 
If the value is less than 0, I put it in red, and if it's green positive. 

I created a KPI where I inform, if less than 0, I assign a value, otherwise 
I assign another value, then assign this KPI to the card and 
I was able to put it to work without major problems, save and close the dashboard. 

Today after opening the same, it simply stopped working. 
The KPI brings the correct result and assigns the value, but the coloring does not work at all. 
I am using the new version (2.50.4859.502 64-bit)

can you help me?

Priscilla