If you have subscriptions such as iCloud+, have an unpaid balance or use purchase sharing, you must keep at least one payment method on file. Do you have a subscription? You can cancel iCloud+ and cancel other subscriptions from Apple.
How do I remove my card details from my Apple ID?
Open the Settings app. Tap your name. Tap Payment & Shipping. Tap Edit, tap the red Delete button, then tap Remove.
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