aaVowel in converted Win is still a unicode character in particular words

[knwin]

when convert unicode အဓိဋ္ဌာန် to win. aaVowel is not converted to "m". Instead it is still the original unicode character aaVowel.

convert('အဓိဋ္ဌာန်', 'unicode', 'wininnwa')
't"d|ာef'