Help Internet 4G and upgrade problem

[MannOmanx]

Hi guys,
I bought a new phone, an LG E975 Optimus G.

1. It is version 4.1.2 and wondered if there is an easy way to upgrade without having to change the configuration on the phone, ROMs etc. Tried this but every guide is very difficult to follow.

2. My previous phone was 4G which worked fine, but when putting my 4G able sim card it reverted back to 3G. The phone is apparantly 4G enabled but when searching the LTE option in the network settings is not there as suggested online. Is there another way?

Please could you help out an Android newby??

 

[AZgl1500]

The sim card, just possibly might not be compatible with that phone.

I acquired a Note 4 and just switched the sim card out of my S5 to the Note 4.

3g, but no 4g...

went to Verizon's store and the said they the sim card is bad.
put in a new one, and now I have 4g

 

[chanchan05]

1. No. This is a cheaper end phone and is unlikely that LG made updates for it. Hence ROMs are your only hope.

2. See previous reply.