Apologies for the unexpected increase in resource usage costs. I assume your billing concerns have privacy dimensions so the best channel to address these concerns is via dedicated (1:1) channel via our Azure billing support team and not the public forum. The billing engineers are in the best position to review your your overcharge (costs) concerns and provide an amicable resolution based on their findings.
Follow these steps to raise a billing related support request at no extra cost to you. Let me know if you have any followup questions.
Cheers.