Embedding does not work

[seokai]

Embedding from Gutenberg does not work on all of my sites.

If I try to embed for example a video from youtube, the request gets a 404:

api-fetch.min.js:2          
GET https://www.example.com/wp-json/oembed/1.0/proxy?url=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3Du-xuLu6BMk4&_locale=user 404

The JSON-Response is:

{"code":"rest_no_route","message":"Es wurde keine Route gefunden, die mit der URL und der Request-Methode identisch ist.","data":{"status":404}}

[seokai]

Was an issue caused by a plugin.

[peterwilsoncc]

Thanks so much for following up, it's greatly appreciated.