You need to pay what you owe and optionally request a refund. See How apps, content, and subscriptions from Apple are billed - Apple Support which says:
“If none of your payment methods can be charged, your account shows a negative balance. You can't buy, download, or update more apps or items until you update your payment method.”
You can contact Apple ( Contact Apple Support - Apple Support ) but the standard resolution in this case is to pay what you owe and then optionally request a refund.
- Refer to Payment methods that you can use with your Apple Account - Apple Support to find out what payment methods you can use.
Read this article about how to add a payment method (usually a credit or debit card of some kind) to your Apple Account -->Add a payment method to your Apple Account - Apple Support You can also add money to your account balance by redeeming an Apple Gift Card or App Store & iTunes gift card --> Redeem your Apple Gift Card, App Store Card, or App Store & iTunes Gift Card - Apple Support
This article tells you how to request a refund for apps or content that you bought from Apple -->
Request a refund for apps or content that you bought from Apple - Apple Support
- Note that If the charge is pending, you canʼt request a refund yet. After the charge goes through, try to request a refund again."
- Go to this page Subscriptions and Billing - Official Apple Support to find out how to view your purchase history, cancel subscriptions, request refunds, and for related purchasing services.