I've chosen EN as my default language and all the default setting are set as EN. When I check the site in WAVE(https://wave.webaim.org/) I get this message :The language of the document is not identified or a lang attribute value is invalid. Has anyone else come across this problem? Does anyone know a solution?
Can you please clarify your problem and please give me a screenshot to clarify your problem so I can give you the best solution.
It seems your site does not have some file as en.default.json. Can you check this and let me know, I will try to help you with your problem.