Going from 3G to 5G for VOIP
Yesterday I received an AT&T Wireless Internet modem to convert my Voice Over Internet Protocol telephone from 3G to 5G. When I go to Systems and then to Network I see the modem listed and I'm asked to supply a configuration, a telephone number, an account name and a password.. I supplied "home phone' for the configuration, my home phone number for the phone number, the Account Name from the Modem and the password from the modem. This is apparently not the information that is required because when I click on connect I get a message the device does not exist. I now have no idea what to do. Any help will be greatly appreciated.
iMac 27″, macOS 10.12