Aidyn is over 2.5yrs, and still has a nap during the day, however we have had the odd day recently when he just hasnt gone down for a nap.
What time are you trying to put her down? Can you maybe wait until later to see if she's any tireder?
Have you tried wearing her out in the mornings? I usually take Aidyn on a walk with me to the park or gym (which is over 30mins of walking for him) which is good excercise, plus helps him to sleep better.
Does she sleep in late in the mornings? Whenever Aidyn sleeps in past 7am is usually when he wont have a nap, which thankfully is pretty rare.
Sorry I wish I had more suggestions, but I dont think you are alone...