Fallout new vegas, hostile primm citizens?

i just buyed fallout NV, i started the main quest and after about an hour i arrived to primm since i was following the main quest. then at the entrance of the town the NCR starts to attack me, i dont really care and kill them, then when i enter the casino where all the ''non-hostile'' citizens are, they all start attacking me. I tried to save the deputy, and they still try to kill me as soon as i entre the small casino. Anyone have ideas?