Adding a credit as a "stand-in".

@Peter_pbn​ yeah already tried that help section, no luck.. there isn't an option for "stand-in"

If you're on the page of the title you worked on, click Edit Page, find Additional Crew and choose Add 1 credit, then click Continue at the bottom.

Enter "stand-in" in the occupation field, along with the name of the actor you were replacing, if applicable.

Thanks Peter!