I can't update my Township game

You may need to have a valid payment method on file, even if the app you want to download is free.

If you have set your Apple Account balance as your default payment method, your default payment method will be used first by Apple when you need to make a payment.

Some purchases might require you to have a credit card on file, even if you use your Apple Account balance to make the purchase.

See the following Apple articles:

Add a payment method to your Apple ID -> Add a payment method to your Apple ID – Apple Support (UK) 

Add money to your Apple Account balance -> Add money to your Apple Account balance - Apple Support 

Payment methods you can use with your Apple ID

Payment methods you can use with your Apple ID – Apple Support (UK)

fyi: Not all credit & debit cards seem to work with App Store / iTunes Store, try a different one, or preferably a credit card. If your card is not accepted as a paymenf method, you need to contact your bank.

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