To change the price of your Print Project
Log into your account and go to the Pricing section of your Book Details page to set or update your book's price. Click Save & Continue until you see the Publish Changes Button at the top of the page. If the change is submitted before 11:59PM ET on Thursday, your print book price will update the following Saturday. If your change is submitted after that deadline, the price will change on the 2nd Saturday after the submission.
To change the price of an eBook Project
Log into your account and go to the Pricing section of your Book Details page, click on the Create New Price tab, enter the new retail price, and schedule the price change. eBook prices will update in 24 hours.