What happens if a letter of recommendation contains incorrect info about me?
To be honest, I would consider this to be a major flaw and almost certainly invalidate the letter. It may bring to attention the rest of the application, including the potential that it may be invalidated, too.

In my university, I was faced with a situation in which the reference letter had a discrepancy with pronouns. The applicant was female but the referee was writing using male pronouns (ie., he, him, his). We ran the letter through TurnItIn and found that the letter was cribbed from a source from the Internet. The entire application was rejected.

Admittedly, this is an extreme case. Still, it will raise red flags about your application. Our assessment team is rather experienced in these sorts of issues.

I recommend revising this if possible.