My kids all took discipline to do things that young (I actually didn't start anything before 2 1/2). They were given immediate firm consequences for running, tantrumming, ignoring the teacher etc, that's how they learned not to do it. We enforced rules like that at home from 18 months, so they were pretty well prepared to cooperate in public, but once or twice I had to swoop one off to the restroom for consequence and then return to the class for second chance to act right. No anger, just teaching and consequences so they learned early rather than later.
From your description it sounds like you sort of just watch her do this and wonder why she is. The other kids could be easier temperaments, or they may have had discipline at first.
If you don't want to "force" her to behave, you should probably just yank her until she's older. If you allow it, she'll only learn it's OK to act that way, so it may make more sense to cut your losses and start again later even if you don't get a refund.
It often "seems like" other kids are magically behaving, I've had lots of moms come up to me in classes and say they wish their kids cooperated...but I had to majorly enforce it. Two is pretty young, it won't hurt her to wait a bit for the social classes.
This book is great to prep her for good preschool behavior, Back to Basics Discipline by Janet Campbell Matson. My older two, 3 and 5 were stellar for group stuff from 3 and up with early practice. My 2 1/2 year old is catching on ...with work!