/cgl/ - Cosplay & EGL

I have a few brands (AP, Btssb) and bodyline blouses with these heart buttons. I think I'm pretty standard size when it comes to brand items (90cm bust, 70cm waist) but I find the buttons keep popping out when I'm wearing a skirt and it's been pretty annoying (I do wear a tanktop under the blouse so I'm not flashing anyone). They pop at areas where there's a bit of tension due to my bust and where I hunch over/sit down (stomach area where fabric is looser). According to lolibrary measurements, the blouses I have should have been within my measurement range. Is there any way to fix this problem and is this a common problem?