Make room for the other version
Ask what the other person understood before assuming that you are arguing about the same facts. For a message about how to follow up on a sponsorship request, use this factual base: name the product, proposal, meeting, commercial question, and last agreed next step.
Correct the record precisely
Correct only what you can support, acknowledge any real impact, and propose a practical way to prevent repetition. Add one relevant update and ask whether to proceed, defer, change scope, or close the opportunity. Make the immediate next step clear enough that the recipient can answer without reconstructing the entire history.
Agree on a testable next step
Do not hide an unsubscribe request, invent scarcity, or escalate around the named decision maker. Follow privacy, consent, procurement, and recordkeeping rules for commercial communication. Do not recruit an audience, publish private evidence, or turn a misunderstanding into a campaign about character.