@Sanjeev Singh If you are seeing the issue "The subscription is not allowed to create or update the serverfarm" -If you haven't done retried, please retry creating the resource again.
If the issue continues to persist, for a detailed investigation, we request you to create a support ticket. Please create a support ticket for an immediate and focused assistance.
Please accept as Yes if the answer provided is useful, so that you can help others in the community looking for remediation for similar issues.