To stop charges on an RDS instance you created by mistake, release the instance or unsubscribe from it in the ApsaraDB RDS console. The method depends on the billing type.
Pay-as-you-go instances: Go to the Instances page, find the instance, and choose More > Release Instance in the Actions column. After you confirm the release, billing stops and the instance is moved to the recycle bin. To fully remove it, destroy the instance from the recycle bin.
Subscription instances: Go to the Instances page, find the instance, and choose More > Cancellation of Instance Subscription in the Actions column. In the confirmation dialog that appears, click OK to complete the unsubscription. After the unsubscription is processed, billing stops but the instance remains visible in the console. To fully remove it, destroy the instance from the recycle bin.