I had the same experience. I was working in the USA for a period. I bought a phone there from AT&T. It was VoLTE capable and working there. When I came back to Canada, I went with Public Mobile. I used the same AT&T phone as in the USA and all worked...
I too swapped out the ZTE WF721 for the ZTE WF723 for the same reason ( the old 721 model is only 3G and the networks is shut down or soon being shut down). My ZTE WF723 will connect to the 4G LTE network and place called over it , but once the party...
