Why do i have the tax code BR 1 for both of my jobs?
Unlikely to be Revenue error. What happened when you started both jobs? Did you pass on form P45 for main job, or sign form P46 to say the first was your only or main job? I would say not, if you are on code BR there, unless form P45 had code BR shown on it. That would be possible if that was from a second job. To be more specific, I would need to know more about circumstances of your starting job, and what you were doing from 6th April, until you started jobs. HMRC would not have issued both these codes, unless they had reason to believe you are also working elsewhere, or you are not a British citizen with residency not established. What to do to put it right? Contact tax office at main job, and explain circumstances. Staff may need to know about your employment history, and can tell you what information is needed to get correct code number issued at main job.
