When I try to make a call, this is the message that pops up. Data is working. LTE is connecting. I'm on Tmobile. I went in to the phone settings via *#*#4636#*#* to check the network and it's on TD-SCDMA/CDMA/UMTS. I went to the network settings and reset the sim data network settings and that was what it was reset to. I thought it would be GSM/Auto but that didn't fix it either. Under Voice Serivice it says "Emergency Calls Only". Voice Network type: "Unknown". Is this a SIM card problem or did I mess something up in the settings? I flashed back to stock oxygen and while the phone was downloading the update, I was actually able to call my voicemail. But as soon as I hang up, the message in the title popped back up again. Help if you can.