On another though, Did You attempt to use up your credits by renting the movies etc from your mac/pc, i mean through itunes.
You should be able to do this and then once downloaded you can move them to your Apple TV and play them.
Do you have a credit card setup in the itunes account?
or just the itunes balance?
If you have a credit info set up
First Remove credit card info from the iTunes StoreMake sure it says "No credit card on file" under "Payment Information"
Then try to attempt the purchase again.
Also where you able to check the location setup in your account?
Let me know what happens
Tap Settings on the Home screen.
Tap iTunes & App Stores. Tap on your Apple ID. (If you are not signed in, enter your Apple ID and password, and tap Sign In.)
Tap View Apple ID.
Enter your Apple ID password.
In the Edit section, tap Payment Information.
Update the information that you want to change.
Tap the Done button when finished.
The payment methods that the iTunes Store accepts can be found in the payment type section. If you do not want a payment method on your account, select None in the payment type section.
Let me know if you need any further help.
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