My sister received a letter from child support instead of me?

Is this really okay,my sister received a mail from the ohio department of children services about a child i supposedly fathered with some girl i barely remember.Why did they send it to her instead of me?well they want me to go and take paternity test what will happen if i gnore it?will they send me to jail or susspend my drivers licence.i dont have a job and i am an international student so i dont have authorization to work?i am terrified of all this,i dont know what to do,please advice?