Opinions please............?

I was given a job description when I started my new job in February this year. Over the last month, I have only been doing one part of the job I was asked to do. It is driving me insane - I can't stand it and think it is really unfair. What do you think? Would you put up with this - especially when you know that you have so much potential and have been given the worst job in the department?? I feel like i've been lied to at the interview.