So I was looking into that this morning, and there are number of hidden rules Amazon creates for book reviews. For example, one of the new ones is that you have to spend at least $50 per year with Amazon to write book reviews. There could be a number of factors in hidden rules that can be preventing you from writing a review.
It should not be automatically assumed that reviews are being rejected due to the book's content. It's not impossible (because Amazon is very "left wing" if I may use the phrase), but please don't jump to conclusions. Review scammers has actually been a huge problem for Amazon over the past few years, whether it's with people trying to 1-star review bomb a book with mock accounts (as I already had one lady do who was mad that I wrote a piece exposing the truth about Michael Landon), or with some people even using Amazon reviews to make it onto best-seller lists by buying reviewers, and Amazon has been fighting that battle for over a decade.
If you cannot write one, that's alright. In the end, Amazon reviews don't make much of a difference. Most people that would read my books are going to find it through other means than Amazon. My thought was simply that some in-depth reviews would be preferable and helpful to those who might have found the book on Amazon, but I also have no intention to break any of Amazon's rules just to have some reviews; if you can write a review, great, but if they say "No" to any of you, that's fine, let's just let it be and move on to do our work.