I have Samsung J5 mobile with option for LTE access (4G)
I am now on my 4th sim sent from virgin and still have no 4G access and virgin tell me my phone is receiving a 4G service. I've passed the refresh date. My wifes 4G sim works in my phone but after hours on multiple calls to customer service I still do not have 4G access. Otherwise the sim works fine for calls and texts.
What symbol is showing on the top right? (3G, H+, 4G etc)
Can you access mobile data in general?
If your handset has the incorrect APN settings then this might cause a problem. You can enter them manually by looking here or you can select your handset from the list here and you'll get the update directly.