Try to slow down and think about it from your bosses view. Assuming they are a reasonable person, they don’t WANT you to be sorry. What they WANT is you to not make those mistakes. So instead of saying sorry, consider doing a “retrospective”. Consider what went well and what could have gone better. What lead to mistakes? Can we take steps to avoid or mitigate those mistakes in the future? I don’t know what kind of job you have and it may be impossible to do that on work time. But if you come to them with and understanding of what lead to mistakes and a plan to improve, they will be more interested in that than you says sorry 50 times.
Please note, I understand this is a challenging ask. But making significant improvements in life usually are. Also results are not instant or permanent. It’s a process you keep working at, but get better at over time.