I was so frustrated trying to get through prior to our departure. The site does not work properly. I would try and try to gain access, but mostly to no avail. A fax to Princess asking for help brought absolutely no response!! They know how to cruise, but not how to look after a web site with problems.
The problem with the booking function of the Princess web site seems to be one of inadequate server capacity. On one of my cruises, I finally got through on the third try.
It's important is to let Princess know that it's taking several tries to get through. If enough of us do so, the people who maintain the web site probably will come to understand that there's a problem and will do something to resolve it.
I had no luck getting on the server the first time I tried. I think I attempted over a weekend with no luck. Went back on line Monday a.m. and VOILA, it worked! If push comes to shove, I think you can just fax your info to Princess. A couple of people I talked with on our cruise did this and were successfully. Good luck