I was charged with felony that I didn't do, what should I do?

I was employed with a company in Arizona. I quit to go back to school in another state. Upon quitting I was contacted by the company that I was accused of credit card theft. I told them I had done no such thing. They said they would investigate it and let me know. I never heard back from them. I applied for a job while here in school and was turned down because I was told that I had a pending felony charge for credit card theft in Arizona. But I did not do this. They also have warrant for my arrest. I dont know what I should do? Will the pending charge eventually drop? I'm innocent.