it should be fairly easy to fix. Once you find out which agency has the bad information, send them a letter by certified mail that includes the page from your report with the bad date highlighted, a copy of something with your birthdate on it ( a driver’s license) and a nice letter.
The address and birthdate information on these reports usually comes from information one of your creditors punched into some system. Someone could-have fat fingered a key and it got onto the credit report.