When an Amazon Kindle Author sets a price of $2.99 or above, the author can choose a 35% royalty or a 70% royalty. It is easy to make a mistake and set the wrong royalty. For one thing, the 35% and the 70% royalty can both look like $1.05. Why? Because you see $1.05 listed first when you choose the 70% royalty for a $2.99 book. It is easy to think that delivery costs or other costs are factored into the equation and $1.05 is what you get. My sister made that mistake and lost thousands of dollars because of it. People preordered thousands of copies of one of her books before she recognized her error, and so she lost out on $1 for each of those thousands of preorders. Why can’t Amazon simply automatically make the royalty 70 percent for Kindle eBooks priced at $2.99 and above? The answer is probably that Amazon makes lots of money from the innocent mistakes of authors. So, if you are an Amazon Kindle Author, make sure that you choose the 70% royalty if you price your eBook at 2.99 or above. If you work for Amazon in this particular part of the company, why not work to automatically make the royalty 70 percent for Kindle eBooks priced at $2.99 and above? 
See the Units Sold? If they are for the 35% – promo, each unit sold has a $1.05 royalty for the author instead of a $2.05 royalty. Most of these sales would have had a $2.05 royalty. 
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Thank you for writing to them. You are an amazing person and brother.