I take a flight in between and want to resume my interrail trip from Barcelona. When i try this on tripplanner i can't plan it without having to have a trainride from Milan to Barcelona.

Hello, i have a question concerning my planning. I have a plan going from belgium and having a roadtrip in Italy. But i have flight from milan to barcelona . I want to resume my interrial trip from barcelona. When i try this on tripplanner i can't plan it without having to have a trainride from milan to barcelona. I don't want this because i have flight but would like to resume my trip from barcelona.