After travelling to a few different countries I returned home to have only 3g. I've tried all the usual reset of networks, removal of sim etc so a replacement SIM was suggested. This arrived, but no luck. All the same possible remedies tried.
I don't have the option to see APN settings (iphone 5) so can't manually add these.
What's strange is that while I had this issues when my number was porting over from EE, it did resolve itself, so I know it's nothing to do with the phone or previous profiles etc from another provider.
I'm out of ideas - anyone have any suggestions? (Other than moving on from plusnet)