One of the things I do in calling Senators offices is ask for the aide who handles immigration matters. There is such a person on staff, sometime they're called a deputy. It isn't easy getting a name or even getting transferred, but it lets them know you're onto how the office is structured.
I also ask whether they are typing or writing down what I am saying, and how often are these comments shown to the Senator? Do you show all the comments to him or her? I pin them down as to how they handle the calls. I try not to accept a brush off.
Good advice. Thanks for the tips.