Moto G bottom right opens

I bought a Moto G a few days ago and the bottom left side of the back case wouldn't close. So I returned it. Now I bought another one and noticed today that the bottom right side of the case at the back is open. It seems loose as well. When I close it it doesn't click and seems loose and so no wonder I found it open. Should I return it? I am tired of Moto G and this problem.