name & identity assumed by another person

[skat22]

I am often confused with another person, and this person has been using my name and pretending to be me. We look so much alike that people think we are the same person. I would like to know what I can do to protect myself against this person assuming my identity. I am afraid that this individual will try to access my bank account and credit cards. I know this person's first name, but nothing else. I live in Indiana.