APS witha B.S in Mathematics?

Hello everyone.

I would like to know how difficult it is to be an APS? I have applied for months through multiple applications, only received two interviews, and one interview cancelled. Is my degree holding me back? Does saying in the application that I have done general biology, chemistry, physics, and calculus courses help me? Would putting in my application that I have a minor in Biophysics help me out? I graduated 3 years ago. I've been working retail after graduation to help family with making ends meet. Can you give any advice on how to better my chances of getting interviewed? Would being an air resource technician be a better route?

Thank you.