The Invisible Mr. C

For the past four weeks, I have been trying to get in touch with D C, my caseworker at the Crawfordsville SSA office. I am an SSI beneficiary in good standing, and this guy will not answer my phone messages, physical messages left by other office workers, or even REGISTERED letters. The other people in the office say that no one else can help me, as he is the only caseworker. They also refuse to give me an e-mail address, saying that there are "virus" concerns. Can anyone give me any advice about who to write to in order to report this problem? I am sick of being ignored, and am about to be homeless thanks to the fact that this person will not contact me. -FRUSTRATED IN INDIANA