Correcting/deleting credit issues

I’m running into the problem of correcting a credit I have to reflect the accurate role I did per episode. When I click correct/delete, the next page tells me I have to add. There doesn’t seem to give me an option to correct/delete. Either this function is gone or it keeps misdirecting me to the wrong page that adds credits because there is no differential to the “add credit” and “correct/delete” page. Please advise.