I am experiencing that same behavior that Roadblocked is having in this thread: 4G Network Extender is NOT compatible with iPhone 7 - PLEASE HELP .
If I reset Network settings, the phone will reconnect to the 4G Network Extender. If I attempt to make a call, it disconnects leaving me with no service. It will not re-connect to the extender until I either reboot or reset Network settings.
The network extender that I am using is: Samsung 4G LTE Network Extender - Verizon Wireless .
The phone I am using is Apple iPhone 7 Plus 256GB.
Tengo HD Voice enabled on the account and the device via Settings>Cellular>Options>Enable LTE>Voice and Data.
Also, I have WiFi Calling active as well.
I can also confirm the extender is working correctly with other model of phones such as Samsung Galaxy Note 5, Iphone 6 Plus, Iphone 6.
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