Hi

If you have done maths till BSc 2nd year you are eligible for this course at a reputed institute like IIT guhawati , even I have done MSc physics and maths till BSc second year so even I was eligible for MSc maths in Mumbai university and there is not much difference between MSc maths and maths and computing, this i mentioned to reassure you. Shortlist institutes and colleges you wish to apply offering this course and enquire or get in touch with the institutes individually if they ask for BSc maths or if you don't fit into their eligibility criteria. As I understand you are eligible for this course.

Here is the link for IIT just in case you need it

https://www.careers360.com/university/indian-institute-of-technology-guwahati/msc-mathematics-and-computing-course

Get back in touch if you need any further help with this.