First how do you know you have sales on Amazon? If you're using Novelrank, it has been known to be incorrect but it is usually pretty good. Sales on Amazon are reported on or around the 7th. I did have a couple of ebook sales that didn't show up once and support said that they are sometimes a month behind. So give it a couple of weeks and then maybe contact support.
You can go to Novelrank.com and add the info there and it will show sales or not. It is not 100 percent accurate but helps. Also does your book show a sales ranking on Amazon page where the book is? If not there are no sales. Also you can create an Author's central page on Amazon to check sales. It works mainly for paperback though. Novelrank will check for both.
has the sales report come in then, I have not had mine yet.
The sales reports were in last week Friday, earlier than usual.