This thread is resolved. Here is a description of the problem and solution.
Problem: When I try to access the APIs, the default language posts are displayed in all languages.
Solution: Make sure you are using the latest version of WPML and that you are using the same URL format to access the API. For example:
If you are using URL format as directories: - site.com/en/wp-json/wp/v2/posts?per_page=3&status=publish&_embed
If you are using URL with parameter format: - site.com/wp-json/wp/v2/posts?per_page=3&status=publish&_embed&lang=en
To see the current URL format for your site, click on the WPML > Languages > Language URL format.
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