Resolved Comments Reappear in a Document
You resolve a comment, and later it is back as if you never touched it. An old version, a collaborator's reopen, or a sync conflict usually brings resolved comments back to life.

TL;DR / Quick Fix
Quick fix: resolve the comment again, then check the comment history to see who reopened it or which version restored it. Then confirm everyone works from the same current file, so old copies stop resurrecting old comments so old copies stop resurrecting old comments.
Follow these steps
- Resolve the comment again. Click resolve on the returned comment. A fresh resolve clears it, and the history will show what happens next.
- Check the comment history. Open the comment's history or activity. It often names who reopened it or shows that an old version restored it.
- Ask the collaborator who reopened it. If a person reopened it, ask why before resolving again. They may have had a reason, and a quick chat beats a resolve war.
- Confirm everyone uses the current file. Check that nobody works from an old emailed copy. An old copy synced back can restore comments you already resolved.
- Check for a sync conflict. If the file syncs across devices, a conflicted copy can merge old comments back in. Resolve the conflict in favor of the current file.
- Resolve in one final pass. Once the cause is fixed, work through all returned comments in one pass. A single clean pass ends the cycle.

What NOT to do
- Do not resolve the same comment five times blindly. Check the history first, since the cause keeps bringing it back.
- Do not fight a collaborator through resolve buttons. Ask why they reopened it, since a conversation fixes what clicking cannot.
- Do not work from emailed copies alongside the shared file. Old copies are the classic way resolved comments return.
- Do not ignore sync conflicts. A conflicted copy can undo your resolves silently, so settle conflicts in favor of the current file.
Frequently asked questions
Why do resolved comments come back?
Because someone reopened them, an old file version synced back, or a sync conflict restored them.
How do I see who reopened a comment?
Open the comment history, which usually records who resolved or reopened it and when.
Can an old copy really restore comments?
Yes. Syncing an outdated copy can merge its old comments back into the current file.