Can I change just one instance of an object?

I’m kind of a noob to AS3, so if I’m using the wrong terminology, I apologize. Anyway, is it possible to dynamically change one instance of an object without effecting the others? I’ve created an input text field in the library and when the user hits the “add text” button, it adds an instance of the input text field to the display list. They can then format the text how they wish (color,alignment,etc…). When they hit the “add text” button again, a new instance of the input text field is added to the display list, but when they try to format the new input text field, all of the fields are effected. How do I get around this?