@ataxlab canary , Apologies for the delay in response. Azure charges ₹28.819 per million for first billion DNS queries/month and the additions DNS queries (over 1 billion)/month are charged at ₹14.410 per million. I see there are minimal possibilities here to enforce a monthly quota here on this cost. But, you can always check about the quota increase or maintenance issues by contacting Azure support team.
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