There are at least three known artists with this name:

1) Nicole Zefanya, known professionally as NIKI, is an Indonesian rising R&B singer-songwriter under 88rising label–along with another rising star fellow Rich Brian and Joji. She has written songs since she was 13 and produced her own music which she uploaded on Youtube, as well as her soothing cover songs.

2)Niki aka Kairit Tuhkanen is Estonian Pop singer. Her songs are taken from Russian Pop artist Zhanna Friske.