Hear one language and read another
Original voices with translated subtitles are one option. A dub with captions in the same language is another. Select both settings in the viewing app according to what helps you follow the story.
When only some lines are translated
A track intended for selected foreign-language passages will not caption every conversation. Choose a fuller available track if you need continuous text. Its language name alone may not explain its coverage.
Legible text on your screen
If the player allows customization, adjust size and outline from your usual seat. Test against a bright scene as well as a dark one. Avoid making the text so large that it hides important parts of the image.
Dubbed dialogue and captions do not always match word for word
Different translations can phrase a line differently. Confirm your chosen tracks before assuming the movie is incorrect. Production name and year help distinguish a real title mismatch from a language-choice issue.
A timing problem
Use a synchronization adjustment only when the player supplies one. Different film edits can have different timing, so a subtitle file matched by title alone may not belong to the edition you are watching.