Why does this keep happening? (VoIP not connecting)

[Geekofbroadband]

Anytime the router is restarted or factory resetted, theres a high chance randomly the VoIP simply won't connect at all, even after we leave it on its stuck on "Service not ready". And it will only come back after we try multiple restarts and resets, it's very annoying.

[Schockwave]

@Geekofbroadband , have you checked settings, also have you tried unplugging and re plugging the voip phone? I do not have a voip phone, so no idea, but just trying to help and making a suggestion.