Hi and Welcome. My Name is ***** ***** I look forward to assisting you today with your question.
Are you sure you want to cancel the iTunes account ? Because everything of that account will also be deleted including all purchases ever made.
The best option is, go ahead and change your Apple ID password ***** here --> http://iforgot.apple.com/
or you can remove the credit card info from the Apple ID, see here--> https://support.apple.com/en-in/HT201266
If you have any questions or would like any additional information, please don't hesitate to ask.
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