Samsung Grand Galaxy Prime Clone 3G problem

[Akan]

Hello,
I have a Samsung Grand Galaxy Prime clone. I recently used SP Flash Tool to flash a stock rom to it successfully. However the phone now fails to detect nor connect to 3G networks which it was doing before I flashed it. It can only connect in 2G/Edge which is too slow to be of any use.
I've tried setting GSM/UMTS band to Automatic, Euro, Japan, Aus, Aus2. That hasnt worked.
I've tried setting Network selecting mode to GSM/WCDMA auto, preferred. That hasn't worked either.

Here's the phone info;
Hardware : MT6572
Model : SM-G5308W
Build number : ALPS.JB3.MP.V1
Build date UTC : 20150713-165554
Android  v : 4.4.4
Baseband v: MOLY.WR8.W1315.MD.WG.MP.V1, 2015/07/09 15:58
Kernel v : 3.4.5 (root@xing2015-desktop) (gcc version 4.6.x-google 20120106 (prerelease) (GCC) ) #1 SMP  Sat Sep 5 16:40:30 CST 2015

Any help will be appreciated.
​Thanks in advance.