Calls not hanging up after the customer hangs up

[Fernando Carvalho]

We have an on premises 3CX server with the last version 16 running on a Windows Server 2019. All agents are using 3CX softphone v16.
I just noticed that when we make outbound calls, if the customer we call hang up, the call doesn’t drop, so my agents keep talking for sometime until they realize there’s nobody on the other side anymore. And we are only calling to cell phone numbers.

I never realize that but I tested and indeed it happen with any extension.

Is this something we can fix?

 

[cobaltit]

Yes. It sounds like you aren't using a supported SIP provider with the 3CX template. This is a scenario that is tested during interop. Using one avoids these types of issues. Otherwise make sure your firewall checker passes and then you'll want to get a wireshark capture of this happening and talk to your provider. Most likely you'll need to play with the trunk settings and re-invites/replaces.

 

[JohnS_3CX]

Hi Fernando,

If the customer hangs up first, then the PBX has only one way to know about it:

- Your provider must send a BYE message -

If this does not happen, then the call has not officially ended and the PBX rightfully keeps it alive.

To be sure, you can run a capture from the Activity Log page and repeat the scenario to find out what really happens like @cobaltit said and then talk to your provider if needed once you have the evidence.

The firewall checker should also tell you if it detects SIP ALG on your network (which can also interfere with SIP signalling).