Hi Basil, I have the same issue. Called the support and they told me that it is related to the 3G network being disconnected. Although my phone supports 4G they said that if my phone does not support calls over network, I won’t be able to make calls and I have to buy the latest model.  For me it is absolute nonsense as the phone is just 5 years old. My phone is ASUS Zenfone 5. Could you suggest maybe some settings change or enabling SIP calls etc? Thanks. ... View more