contacting Mt Pleasant Texas office

I recieved a letter dated 11-21-11 telling me to contact office. I have made several voice mail messages and severa attempts to contact office by phone as asked to do by 11-28-11. No one returns calls and I have waited as long as 10 minutes on hold to no avail. Is that office so understaffed they cannot respond in a reasonable amount of time to their clients? How am I to meet the time frame if I cannot even speak to a worker? Being disabled it is hard for me to go to the office and wait in a cold lobby for my ticket number to be called. Is there another way to contact this office, can't something be done to simplify this process.