I've never heard it before but I like it!
It reminds me of
Anka so I thought it was also a diminutive. The -nka part makes it sound youthful.
Possible siblings:
AstridHanneloreGretaElisaMargotMarinaHedwigJohannaRosaAlina
BertrandEdgarFriedrichArnoFranz
~☆
June Song Recommendation☆~
Jungle - "Keep Moving":
https://tinyurl.com/2s3scusa