No Service

A

AC Question

Phone : Lg G3 ( d-855)
Ever since i installed the cloudyG3 2.5 and i've been having no SIM service, not to mention that cell standby is draining my battery like crazy trying to find a signal.
The phone is identifying that there is a SIM card inserted, it just doesn't connect to the network to provide service.
So would changing the software back to the software that came with the phone solve the problem? I think the software's name was V21a-ANE-XX?
Thanks.

P.S the SIM card works on my brother'a phone.