I can't buy gamepass with my account balance

It's not an error. It's the ridiculous system installed by MS. Even if you have enough funds, you need to supply creditcard or paypal information, even if you want and select 1 month. This is because MS sets as default that the subscription will be renewed
without asking for permission. You can disable this after you have a subscription, but not before. So MS forces you to provide creditcard information.

In short, no, you can't get a subscription only with store credit.

The only way is to get pre-paid cards for gold and gamepass if you don't want to provide your creditcard information.

This is the reason why I will never get gold, game pass anymore. It's a bully tactic. MS can change this today if they wanted, but they don't, because they hope you forget to cancel your subscription so they can take money from your creditcard without letting
you know.

Evem thought you're not planning to pay for the following month, making the purchase starts a subscription so the system wants to male sure you have enough funds to cover that. Until you do, it will not let the purchase go through. You can still turn off
auto-renewal after completing the purchaee but you would still need either enough funds in your account for the next payment or a credit card/Paypal on file.

Hi,

I believe your a required to have another payment option liike paypal/creditcard for signing up for subscriptions

Since it starts a recurring subscription, you have to be able to show you can make the next payment, even if you plan on turning off auto-renewal. So you need another payment method on file as well.

Usa paypal, eso lo puede resolver.

:3