UCLA had a 4% admit rate for 2022 CS Transfers with an UC GPA admit range of 3.94-4.00 (25-75 percentile). Your chances were very low to begin with and I agree with @tsbna44 that you really do not have a solid basis for an appeal. Mentioning mental health issues can be a red flag and B’s are still solid grades. Hopefully you have other options and your dream school(s) are those schools which accepted you.
Best of luck and I would move on.