Describe the concern with the evidence you have now. A clear opening can identify relevant services without a completed explanation of every older account detail.
Say what needs attention in the account
Explain whether paying is difficult, a letter needs clarification or a source amount appears inconsistent. Mention the period if known and keep the actual document nearby when practical. A missing record can remain honestly named rather than reconstructed from memory. You can ask for help while questions remain open, before a formal process is assumed suitable or an extensive history is assembled without an understandable purpose.
Give proposed assistance a useful next task
Ask what the work covers, what it costs and why further information is needed. Clarify who would obtain outstanding records or perform a response if that is part of the scope. Keep received IRS directions available alongside any working note. The next conversation should return to relevant evidence, preserving gaps and uncertainty while the particular requirements of an account or formal request still need consideration.