Waste of time in promoting Amazon Affiliate links

Olga: I recommend books to some of my piano students. I sent their parents the books with the Amazon affiliate link and they purchased those books. I saw an increase in clicks due to that, but no sales. Why? 

Olga: Sir, did you find out why you were not getting sales?

" Video where I posted my experience for no earning with Amazon: https://youtu.be/1shV9THcYKA " 

Dear Olga, It is tough to know the reason. I asked Amazon representative to provide me data so that I can know the names of countries from where visitors are clicking on Amazon advertisements which are displayed on my YouTube channels and websites but representative informed me to have no access to those data. So it is imposible to know if you are earning commission or not. In my case traffic is totally organic. My youtube channels and websites receive clicks on Amazon product links. Up to now I never recommended any one to do purchase and very few time (may be in 2-3 months one time)  I shared amazon links with social media.