Princess' upgrade process is outsourced to a third party (Plusgrade). You're getting scripted, unhelpful answers because no one at Princess has direct control of or visibility to your upgrade bids, or direct control of the upgrade process on any sailing.
The bidding/upgrade process is to set up to be entirely online and automated, so it's not surprising when Princess employees tell you there's nothing they can do, because the process isn't meant to be manually manipulated or subject to Princess employees trying to figure out why you didn't get an upgrade but someone else did.