Someone else feel free to correct me if the name's wrong. I sometimes have a hard time telling where to separate parts of words in Japanese names.

久寝ねねこ -> Hisa Nene neko
I'm no Japanese expert, but there's 3 "ne" here. The first one being written with 寝 which is the character for sleep. I'm not quite sure what the 2nd one is used for, maybe emphasis/accentuation of the "sleep" part. From what I've learned of the language so far, it doesn't seem to change anything to the meaning if you remove it. So I think it makes sense to go with Hisa Neneko.

In one of her first videos, she clearly introduces herself as Kusumi Neneko. Furthermore her twitter is kusumineneco_mr.

Oddly, sumi should not be a reading of 寝, nor should there be any similar kanji with that as a reading...

Though, it's not like they have to use a standard reading in names. 夜神月 (Yagami_Light) is one example where they took some liberties. There are plenty of others, though I can't place any right now.

For some reason, I don't remember that Twitter link being on the source page. Thanks for fixing it though.