A recurring $2.99 charge is usually the Prime Members monthly fee for the Kindle Free Time subscription for one child. A $6.99 charge is for Kindle FreeTime is for up to four kids. A $9.99 Amazon digital services charge is usually for the Kindle Unlimited service. A $99 Amazon digital svcs charge may be for Amazon Prime. At the end of the free trial period, Amazon Prime goes into annual membership and is charged at $99 automatically for the next period. You can cancel your Amazon Prime on the Manage Your Prime Membership page.