Sometimes non-native speakers of English see certain phrases, such as "Imma be," being used by native speakers, and assume this is just modern English slang, available to anyone. But many of these usages are specifically #AAVE (African American Vernacular English), and if you are not #Black and you use these, you might be criticized for #CulturalAppropriation. The mistake is of course an innocent mistake, but that doesn't mean you aren't accountable at all. When you learn that a particular phrase (such as "Imma be") is AAVE and are called out, apologize, say you didn't know, and stop using it. Don't become defensive and try to argue that it's okay for you to use it because [reasons].