I cannot get Wi-Fi calling to work with the SBG7400AC2. I have Vyve cable internet and Verizon cell service. This modem is new, and I had the same problem on the previous Surfboard that we were renting from the ISP. Also, I had this problem on my older phone (Galaxy S8+) and thought it was because the phone was so old, but same thing is happening on the new phone (Galaxy S23 Ultra).
I initially set the modem up using the Surfboard Central app and just accepted defaults. I did just login to the web interface to see if anything was blocked on the firewall. A Google search suggested enabling IPSec, PPTP, L2TP, and VPN Service for a Netgear router. Under Firewall settings, IPSec, PPTP, and L2TP pass-through are enabled. I can't find anything related to a VPN, and I can't imagine that would be the issue.
This would be merely a nuisance, except often I'll miss calls and cannot send or receive texts when the phone has decided to try and use Wi-Fi calling. The workaround once I've realized it is to turn Wi-Fi off on the phone, but that's not really a solution. I had turned off Wi-Fi calling, but I use it at another location where there is no cell signal.
Any suggestions are welcome! Thanks.