Azure enforces rate limits on creating subscriptions to prevent abuse and ensure service availability. This is why you are encountering throttling (rate limit), after creating multiple subscriptions within a short time frame. The "TooManyRequests" error is Azure's way of signaling that you have hit this limit.
Azure rate limits are usually temporary. They reset automatically after a cooling period, which can range from minutes to several hours (sometimes longer for subscription creation). Since you already waited 12+ hours, try again after 24 hours.
When using the Azure Management API, implement retry logic with exponential backoff. This ensures your retries do not overwhelm the system.
Sometimes, limits may be specific to your test tenant or directory. If possible, try creating the subscription in another tenant or check if policies like Management Group limitations are affecting subscription creation.
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