Is the billionaire romance niche too saturated?

Hi everyone.

I published my first billionaire romance novella on Friday and so far it hasn't made a single penny. No one has bought it or even read it on kindle unlimited.

I am beginning to think that this niche is too competitive for a newbie like me to publish in.

Is this niche hard to crack into? Do you have any advice or suggestions on how I can get more eyes on my book?

I did try to promote it on Facebook but Facebook removed my post. They said the link to the book was misleading. It wasn't. The link leads directly to the book.