The normal Norwegian language is supported by Bing, however the language package you installed for your site has language code that does not match with Norwegian language code in Bing.
In the language manager page, see the language Tag column, you can see language Tag of Norwegian is nb-NO, which “nb” refers to language code and “NO” to country code (see the language code column, in Bing, the Norwegian’s language code is no).
Please check in Joomla community to see if it has a Norwegian language package that has a language tag is like ‘no-NO’. if it does, you can download and install it for your site.