When I first got activated, my 4g was working and I had voice bars so I thought I was good, but it turns out I couldn't make calls or texts, no other data either except on 4g. I called virgin again and after informing them that I had 4g but nothing else, they transferred me to another guy, who said all those features were disabled on my account, for some reason. He re-enabled them and all was well. Call them back and make them figure it out, you shouldn't have to enter any codes or stuff like that to get the basic features working.
hurricane I had error 64 sending texts too. Do you get a "3g" indicator in your status bar if you turn off 4g? You should, if not call virgin and tell them that.