- Make sure you are clicking the “Comment” button to publish the comment after typing it. Unpublished comments will be lost if you close the document (Search results 5, 7, 12).
- Check if you still see the comments in the document’s comment history. Comments that were saved and resolved may still be accessible this way (Search results 5, 7).
- Try making a copy of the document without the resolved comments and continue working in the new copy. There may be a limit on the total number of comments stored in a document’s history (Search result 8).
- Issues could be caused by browser extensions interfering with Google Docs. Try disabling extensions or using a different browser (Search result 9).
- Weak internet connectivity could also cause problems with saving. Make sure you have a stable connection (Search results 1, 9).
In summary, the most likely issues are unpublished comments, history limits, browser/connectivity problems. Check these first. Making a fresh copy of the doc is the nuclear option if issues persist in the original. Reaching out to Google support directly could also help diagnose and fix stubborn problems with comments not saving.