@lilypearl While I have not found erroneous information in my own medical record. This has happened to my husband, who is a retired MD. We figured out that information included in his medical record that was never discussed during his visit resulted from the PA working from some kind of template and not reviewing the information carefully enough.

The best any of us can do is to read our own medical record/note as soon as it is available. If we find errors we contact the physician or practice office, point out the error(s) and ask for a amendment since as others have written above Electronic Medical Records cannot be changed. If one's medical record is not amended as requested then the next step is to ask for the Practice Manager and work with this individual. If that still does not work and the practice is part of a large medical center then yes, contact Patient Relations. At Mayo Clinic this is referred to as Office of Patient Experience:

-- https://www.mayoclinic.org/about-mayo-clinic/patient-experience

I view working with an attorney as a last resort as it can cost money. However, it's possible that a short conversation with your attorney will result in a letter to the medical practice and you will get a quick result.

I agree there should be no errors in one's medical record. Would you feel comfortable giving us the kind of error you found? As @denisestlouie indicated her error was a very serious one as it was an incorrect diagnosis.