Reconcile two lists in Excel and surface the mismatches

I have two lists in Excel that should match but do not, and I want Copilot to tell me exactly where they differ.

In Excel, open the workbook with both lists. Open Copilot.

Sheet A and the list A range: {{list_a}}
Sheet B and the list B range: {{list_b}}
The key column to match on: {{key}}
The value column to compare: {{value_col}}
Tolerance (exact match vs. within X): {{tolerance}}
Known reasons for mismatch (timing, rounding, partial refunds): {{known_reasons}}
Output sheet name: {{output_sheet}}

Ask Copilot:

1. Match every row in {{list_a}} to {{list_b}} using {{key}}.
2. Produce three sections on {{output_sheet}}:
 - **Matched** (key in both, value equal within {{tolerance}}). Count only.
 - **Mismatched** (key in both, value differs). Full row from each side, side by side, with a Difference column.
 - **Missing** (key in one list only). Which list, what value.
3. For each Mismatched row, suggest the most likely {{known_reasons}} reason and a confidence level.
4. Summary at the top: total matched, total mismatched (with $ impact), total missing in A, total missing in B, the one mismatch I should look at first.

AU English. AUD. Date format DD/MM/YYYY.