From time to time, the retailers will temporarily discount the price of your book. You will know that your price has been discounted when the original price is crossed out and a lesser price is displayed.
Retailers will temporarily discount your price to drive more traffic to your site and encourage more sales. Unfortunately we are unable to control when this happens, or with what retailers. The good news is, this discount does not impact your royalties and you will receive the royalty owed under the original price.