Bonswa Mesye Rachal,
Yes you are right. “fi a” is more prevalent. Some people from certain regions tend use nasal vowels especially with words ending in “i” ….zanmi, fanmi, mi, fi, etc …..
And one of the reasons for this is they’ll do that if the preceding syllable has a nasal sound like fanmi, zanmi, kanni, ranni, etc…..
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