Default I bought DG500 phone and the 3G doesnt work for me

Hi, I bought DG500 (doogee) phone and the 3G doesnt work for me.
is that possible to make it work ? it by my understanding is MTK 6589 chipset and I think i need to edit somehow to APN (but I have no idea how to get there I am noob. the Android version is 4.2.2 help.

by the way the Phone is working and I can get SMS or Phone calls.

thanks