As many people here, I'm learning Esperanto on Duolingo and it translates pardonu as excuse me or sorry.
Is it possible to translate it as forgive me or pardon me ?
Though "Forgive me" probably is translated in a bit longer form "Mi petas pardonon".
However "Pardon me" ("I beg your pardon") is quite British - isn't it.
The context is decisive on the most fitting translation.