Australia energy bill looks wrong: what should I do first?

Check the billing period, meter number, tariff and whether usage is actual or estimated, then ask the retailer to review the bill. Energy.gov.au says retailers must review a bill when requested, and if the issue remains unresolved the state or territory energy ombudsman can provide free independent dispute resolution. Official source: energy.gov.au. Guide: https://getinstantlaw.com/utility-telecom-billing-disputes