Apple TV audio language is resetting every episode

The series is in English, I’m changing it to Polish when I start series. Then the new episode starts and I need to change audio again from English to Polish. I have changed default language to Polish, but this didn’t help. I’ve read the article about changing subtitles and audio, however the main point is that I don’t want to change language every new episode starts. I’d like to set it only one time when I start series, and Apple TV save my setting for those series. So the question - why it doesn’t work?