Zapier trigger option set data encoding problem

Hi,
In my app I use official Zapier plugin to send some data. As long as used fields are type of “text”, they are correctly sent in utf-8 (with Polish letters, etc.). Unfortunately values set as option sets have a lot of characters (Polish letters, spaces, parentheses) replaced with underscore - for example “Pokój dwuosobowy (2 doby) - 220zł” became “pok_j_dwuosobowy__2_doby____220zl”. As you can see on below screenshot, other text values are encoded correctly.

Have anyone experienced similar problem? Is there any way to fix that?