No,I said a season EIGHTEEN contestant.And she has blonde hair.Search for the season 18 American Idol tv ad on Mnet in South Africa,she's shown in that tv ad on stage playing a black guitar.And she has her eyes closed.You see a guy sitting at a piano before you see her.Here's the link:

https://m-net.dstv.com/video/american-idol-s18-m-net

I don't know the name of the contestant, though have been watching bits and pieces of the new season during the last few weeks, however haven't paid attention to what anyone's name is.

Incidentally, the present season is officially and accurately Season 3 on TMDb (and on ABC, which decided to start the seasons counter over to 1 when the series switched networks year before last; any site considering this Season 18 [which several do] is definitely in error).

Here, on the official ABC American Idol site, you may perhaps be able to find a clip that the person you're wondering about appears in, and that may show her name in a caption while she's performing at some point. Take particular note, on the ABC site, of where Hollywood Week solo-performance clips are presented, as names appear below the pictures.

I figured it out!!!After doing a Google search I figured out that her name is Hannah Sattler.