The IRS sent me a CP12 notice saying they changed my return and drastically lowered my refund, how do I formally dispute their automated math calculation?

Question

Kohari Gonzalez Oneyear & Brown · Accepted Answer

A CP12 notice usually means the IRS says it corrected a math or processing issue on a filed return and adjusted the refund amount. The practical question often turns on what was changed, whether the IRS adjustment matches the return records, and whether supporting documents show a different result.  For an answer applied to your exact numbers, bring this question to a licensed KGOB CPA in a focused session and leave with a clear next step.