Are you sure it is authentic?
Scams (e-mail, text messages, and phone calls) are getting very good at closely imitating true Apple communications. Always be cautious. Here are some guidelines:
Identifying legitimate emails from the iTunes Store - http://support.apple.com/HT201679
Recognize and avoid phishing messages, phony support calls, and other scams - https://support.apple.com/HT204759
If you are uncertain about a message and a resource provided in that message, do not click on any links in the message. Try to independently verify the resource by going to a support page on apple.com and use that to contact Apple or to use the service the message is telling you to use.
This document explains how to 'Change, add, [review,] or remove Apple ID payment methods' on a Mac or Apple mobile devices; click here --> https://support.apple.com/HT201266
Forward email attempts as an attachment (in MacOS Mail use the paperclip icon) to: reportphishing@apple.com then delete it.