Playing in Polish there are ligatures missing for Ś and Ż. See 2 screenshots attached.

These are called iconography's. Ligatures are the combination of letters with a longer stroke.

The used font has the iconography's only for the base European letters.

 

It's this font https://www.myfonts.com/fonts/estudio-ch/espinosa-nova/capitular-i/glyphs.html

so you have to ask the designer to draw the missing glyphs: Cristóbal Henestrosa