An IRS notice can state account information and also ask for action. Keeping those roles clear helps you introduce the concern needing explanation.
Read the account information in context
Find the notice identifier and tax period before interpreting an amount. Retain the source pages and the description surrounding the figure. If another record differs, identify what appears inconsistent without deciding its cause from appearance alone. A clear question can distinguish a received account statement from your working explanation, making proposed notice help relevant even when the older history remains incomplete or the basis of the amount is uncertain.
Keep the requested action visible
Locate the response directions and timing in this particular notice. Your question belongs beside that wording, rather than replacing it with a remembered procedure from another letter. Ask which support would help clarify the point and what assistance covers. Retain any later evidence of action separately from preparation notes. A reading exercise makes the request easier to discuss without proving that a response occurred or an account result was determined.