My dad’s birth certificate had the wrong birth date on it.
Not sure how it happened, but he had to go through a lot of paperwork to get the issue resolved.
It affected a number of things in his life.
My dad too. He was a twin and they got his sister’s date right and his wrong. He died young, so I don’t know if it affected him, but it is still affecting me and he was born in 1911. I have to prove his DOB by going to the 1920 census which wasn’t available at the time I needed the information. It is available now, of course, but it doesn’t seem to matter any more.