This CP05 notice may have nothing to do with any errors on your part.
It's always possible that:
- Someone else filed a fraudulent return using a Social Security number on your return, and they are working to determine which information is accurate.
- There is an error in one of your tax documents that the IRS is trying to clarify with the company that issued it.
- There is an error or mixup in the IRS records that they are working to resolve.
- Your return lists income that they can't find a record for.
Considering the billions of records they deal with, it would be amazing if there were never any questions.
Relax, sit tight and wait. They may never tell you what the issue was, but at least they had the courtesy to let you know that there is a delay.
