American Standard is riddled with reliability and workmanship issues. There is a thread on another site I could show you how many people get victimized by their lack of quality control.
Best advice is to get on the phone with them and ask for new parts like all the other AS owners find out the hard way.
Last two lavatory faucets I've installed were missing parts.
I took out a less than 2 year old kitchen sink faucet due to close tolerances of the trim (stem bore).
Another is a cadet toilet leaving rust stains in the bowl....not in the tank.
And by the way.....cadets are no longer being sold in my area. They offer another cadet 3 I believe and talk about a sloppy flush.
Ain't no lie that history repeats itself; flushes just like a wash-down with the extra bonus of water splashing onto the lid/seat and floor depending on the flush.