evertime i try to buy gold it says that right before i can confirm buying it idk why
You have a billing issue. Either your billing info is not correct, you have an outdated card or owe money and your account has been frozen from purchasing things until this has been rectified.
Go to billing.microsoft.com and see if there is a problem with the information there. If you can't solve the problem there, you will need to call support and ask to speak with billing.
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