Amanda Bynes was, unusually, on her best behavior in Atlantic City yesterday. Sources saw the erratic actress at Revel’s Bask by Exhale spa getting a facial, and (though she wore a blue-and-black wig), one spy said the recently arrested Bynes was “polite to the entire staff,” adding, “Her appointment went off without a hitch.” We reported Monday that Bynes chased a man at Revel she thought was taking a picture of her, and wore a dress with the security tags still attached.