Read the track list, not just the synopsis
A description written in English does not mean an English dub exists. Original language, dubbed audio, translated subtitles and accessibility captions are separate features. Check the selected service’s menus for the edition in your country.
Make the text comfortable
Where the player allows it, change subtitle size, background or outline. Test the result against a bright scene as well as a dark one. On a television, check it from your actual seat rather than judging tiny text while standing close to the screen.
Captions and audio description
Captions can include relevant sound information as well as speech. Audio description adds spoken information about visual action when offered. Neither should be assumed from a generic subtitle label. Inspect accessibility options if one of these features is important to your viewing.
Timing seems wrong
First check whether the same problem continues after a refresh. If the player offers timing adjustment, make a small change and test several lines. A different cut of a film can require a different track, so an isolated file from another edition may not stay synchronized.