Sorry to revire the thread but,
Having exact same issue rn, another input though, I had another carrier when I bought the phone, and on that carrier vowifi was no issue, but after 2 weeks phone started to give server error when I was trying to make a call.
I changed my carrier and since than vowifi is a come and go thing when sometimes in never comes back until I reboot. Even on airplane mode when its gone it's gone.
I am really second guessing my purchase here since where I live connection is not that good.
Having exact same issue rn, another input though, I had another carrier when I bought the phone, and on that carrier vowifi was no issue, but after 2 weeks phone started to give server error when I was trying to make a call.
I changed my carrier and since than vowifi is a come and go thing when sometimes in never comes back until I reboot. Even on airplane mode when its gone it's gone.
I am really second guessing my purchase here since where I live connection is not that good.