YouTube Data API V3 unkownPart "localizations" - youtube

Question

I have been trying to fetch all videos from a playlist using YouTube Data API, which worked like a char; next, I wanted to try and filter videos based on languages, so I wanted to try to include the "localizations" part. However, whenever I do, I get a 400 response stating that "localizations" is "unkownPart". From what I could see in the documentation, I should have my GET request structured properly:
`https://youtube.googleapis.com/youtube/v3/playlistItems?part=localizations&part=snippet&maxResults=${limit}&playlistId=${playlistId}&key=${apiKey}`
Error message in postman:
{
"error": {
"code": 400,
"message": "'localizations'",
"errors": [
{
"message": "'localizations'",
"domain": "youtube.part",
"reason": "unknownPart",
"location": "part",
"locationType": "parameter"
}
]
}
}
"localizations" is a direct copy from the documentation. The GET request works fine if I remove it so I'm confident that the problem is either the order or my parameters, or the combinations of parameters in use (though I couldn't find anything about incompatible parameters in the documentation).
Parameters order goes as follows:
localizations
snippet
playlistId
key
EDIT: link to the documentation: https://developers.google.com/youtube/v3/docs/playlists/list

Answer 1

After sending the Issue Report it was discovered that I had been using the wrong API endpoint. Somehow (I can't remember why) I was using the "playlistItem" endpoint which doesn't support "localizations", and needed to shift to using the "playlists" endpoint instead.
Furthermore when using a combination of both "snippet" and "localization", they should be within the same parameter but comma-separated, however, Postman doesn't auto-convert the commas in the parameters to "%2C" and therefore would cause further trouble understanding the requests. Fixing these 2 steps, it now works as intended.