I just updated to 4.4.3 last night and in the process have lost my ability to send or receive calls/SMS/MMS when connected to 3G.
When in range of LTE my phone operates fine, however when out of range (in my office) I am not able to connect to LTE and instead my phone drops to 3G which has typically been fine. Now however, my phone connects to 3G and has data access but cannot send or receive calls/SMS/MMS. When I pull down on the notification shade it says "Searching for Service."
I have enabled Band 41 and have set it at priority 1. I have tried disabling it to no avail. I have tried placing the phone on Global & LTE (recommended) and still do not have Phone functionality.
I went so far as to wipe data/cache/dalivk and it still is not working.