Facebook Ad Confusion

[Tarser]

I have recently opened a Facebook account for my self employed business. I wanted to advertise my services as a musical instrument tutor, teaching via Skype and Zoom. Facebook offered a 'boost' to a post, setting a budget for my ad etc. I went through the procedure and for a day, the ad reached a number of people and I had a report of how many, how much I would pay etc...Then my ad was rejected. I ploughed through some pages for why this might be. Most reasons were for racist attitudes, profanity, a whole list of bad things. Yet my ad reads like this - with some details removed.

"Hello, I am the author of **********and other (named musical instrument) books. I'm now offering lesson in ************ (instruments) via Skype or Zoom. Please visit my website********for further details"

What on earth could have caused this ad to be rejected??? I have asked for a review but I'm still waiting to hear back.