Why do my nasal vowels sound 'off' to native speakers? I record myself every day.

I’ve been recording myself trying to differentiate between nasalized vowels in Haitian Creole, specifically when saying words like 'kann' vs 'kan', but my Haitian colleagues keep correcting my pronunciation. I feel like my mouth position is wrong, or maybe I’m over-emphasizing the 'n' sound. How can I stop sounding like I’m speaking French with a weird accent and actually nail the nasalization unique to Haitian Creole?