unicode arrows problem

Hello,

i have a problem with displaying unicode arrows. Namely, when published on PBI Service, I can see the arrows. However, other report users only see empty boxes instead of arrows (when hovered over the arrow shows up). I tried to change DAX code, but the problem still presist. 

Do you have any idea how to solve it?

TrendArrow VisitsGlobal = 
SWITCH (  TRUE() ,
 [Trend Visits Global] > 1  , UNICHAR(129145),   
  [Trend Visits Global] > 0 , UNICHAR(129147),
  ""
)

thanks