That doesn't mean the entire song can only be 32 measures...that simply means you CHOOSE 32 measures to sing. You pick a section that shows your voice off the best.
If we're not having fun, then why are we doing it?
These are DISCUSSION boards, not mutual admiration boards. Discussion only occurs when we are willing to hear what others are thinking, regardless of whether it is alignment to our own thoughts.
List some songs, like "Over the Rainbow," "Blue Skies," and "What'll I Do?"
The take-a-way may be to look for classic songs following the AABA 32 bar form from the first half of the 20th Century (Berlin, Arlen, Porter, Gershwin, Lane, Coward, etc.... and you will find many songs for sopranos among them), but even then, as has been said, you may well not be singing the entire songs with verse, repeats, etc..
Of course, usually for an audition, a 32 measure ceiling doesn't mean you can't follow the ordinary process of editing from a longer form composition.
Take a song you are comfortable with (or that you aren't, if you want to take a step outside of the box), and choose the part that you feel best showcases your range, and the best side of you. However, as an above post said, you have to make that cut to 32 bars. 32 bars may not sound like a lot, but you can showcase a lot of yourself in that span. Best of luck!