Challenge an estimated energy bill with your own meter readings

Help me challenge an estimated energy bill using my own meter readings.

My supplier: [name]
What the bill says: [period, readings used, whether marked estimated (E), amount]
My actual readings and dates: [list, with photos taken on the day]
My direct debit: [amount, and any recent change]

Ask me up to 3 short questions first if anything important is missing. Wait for my answers.

Then:
1. A simple sheet layout: date, gas reading, electricity reading, photo taken (yes/no), notes.
2. Where my readings differ from the bill's estimate, shown side by side.
3. A short, polite message asking the supplier to re-bill using my actual readings and review my direct debit.
4. What to do if they don't fix it: their complaints process, then the Energy Ombudsman, in general terms.
5. A monthly reminder routine for taking and sending readings.

Only use what I've told you, leave blanks for anything I haven't given, and don't invent facts. UK English. This is help organising my own readings and wording, not financial advice; point me to Citizens Advice for energy bill guidance.

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