Calls aren't working
Split it in two first: can you not call out, or can people not reach you? They're separate paths that fail separately. And if the call connects but nobody can hear you, it's your browser's microphone.
Who this is for
Anyone with a calling problem.
Call connects but nobody can hear you
This is browser microphone permission, and it's the most common calling problem there is. The dialer runs in your browser, so your browser has to allow it to use your microphone. If you dismissed the prompt (or blocked it once, on any visit) calls will appear to connect in total silence.
Fix it in your browser's site permissions for this site: set Microphone to Allow, then reload. It's per-device and per-browser, so it comes back when you switch computers, and no admin can fix it for you.
You can't call out at all
Check you have a voice-capable number, and that the Voice Connection / Call Control App ID is filled in on the Phone numbers page. The API key alone covers texting; calling needs that second value. A setup that texts fine and cannot place a call is the tell.
People can't reach you
Inbound is a separate path. The number has to be pointed back at the app (which happens when you connect your carrier), and the app needs a rule for who picks up. A call from a known lead routes to whoever owns that lead; a call from someone not in your database needs a fallback agent, or it has nowhere to go.
Test this deliberately with a phone that isn't in your database, otherwise the first real unknown caller is a live discovery.
Related
Where this lives in the app
This is documentation for Virtual Closer. Book a walkthrough or sign in.