State Management :: Creating Each Session Key As A Unique Identifier?

First of all here is my code chunk.

[Code]....

Right now I am creating this session with the session key "PhonePart" which is also the name of object I am passing in as a parameter in first method. In subsequent methods, I use the the same name to retreive and clear session value. My problem is, this approach works fine If I instantiate a single object of the class where these methods are defined and using that object call the methods, but when I create another instance of the same class and calls for instance method AddToSession and pass that instance, it overwrites the session value stored by the first instance of the class as the session key is the same that is "PhonePart".

Considering this scenario, is it possible that I somehow grab the name of the object as string in the calling method say "AddToSession" and create a session with that name? If Yes, then I can do the same in subsequent methods and retreive session value and also clear the session specific to that instance name without affecting the other session values stored by other instances.