Help, Still Singing Through My Nose?

Been practicing to get out the habit of singing through the nose. I've made quite some progress, but still can't seem to work out some vowels; air still flows out through my nose on some words starting and ending with 'm' (like 'my', 'me', 'mind', 'some', etc.) and those ending with 'ng' ('starting', 'confusing', etc.). And, in case this matters, I have pretty thick southern accent. I need some specific guides, pinky please.