1 could be correct. 2 is clearly incorrect, and does not mean anything in English. "Rob" is a transitive verb. In the active voice, the thief is the subject, and the victim is the object of the verb.
They both describe the same event, but they make a different person the center. The first mentions only the person who was robbed. The second focuses on the action of the thief.
You are considering the difference between the active and passive voice, but you are not using the same tense in each sentence. "The thief has robbed me" is active voice; its passive form is "I have been robbed by the thief."
