@cruise2relaxis correct. I had a flight from San Francisco to Rome which stopped in London. The London to Rome flight was canceled. A section of my return flight from Barcelona to San Francisco was also canceled. I had booked through EZAir and had terrific prices so didn't want to cancel and re-book. I called Princess and it took an hour to get transferred to EZAir. Once I got to EZAir (the Princess agent had to get permission to transfer me), it took another hour, but we got it all straightened out.
Word of caution (someone had posted about this). The Princess agent wanted to try to rebook me, but I was afraid that I would lose my price as had happened to another poster. I insisted on talking to EZAir to get the flights fixed.
Good luck!