What is the 24.99 charge for?
Why am I charged 24.99 what service is this for?
Check your purchase history in iTunes and view your subscriptions.
If you can locate the payment or subscription then you can use the options to cancel or request a refund if applicable.
See also If you see an unfamiliar iTunes Store or App Store charge on your bank, credit card, or debit statement - Apple Support and About payment card authorization holds in the iTunes Store - Apple Support.
If you cannot identify the payment then perhaps you are looking at a phishing email.
If there really has been a purchase that you didn't authorize, or you've entered your Apple ID credentials at a fake Apple portal, see If you think your Apple ID has been compromised - Apple Support.
tt2