Dear aspirant hope you are doing well...

yes you can do b. Sc maths again , it doesn't affect your previous degrees. Because both degree are of different time interval. You can do nth degree in your whole life. Many of us doing it. It's not new things. Just like our previous prime minister Manmohan singh and B. R. Ambedkar has pursue many degree Or more than 4 to 5 degree in thier life. Anyone can do the same.

hope it's helpful thank you