Your payment method is not valid in this store. Please enter a new payment method.
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To me it appears you may have changed your country as in Change your Apple ID country or region - Apple Support
You will need a valid payment method for the country where you now reside. The article Payment methods that you can use with your Apple ID - Apple Support provides some guidelines but you may find that is most readily accepted is a credit or debit card from a bank in the country to which your apple account is set.