Help Request: Canceling Attended Transfer with *2 in VitalPBX

Hello, VitalPBX community!

I’m facing an issue when performing attended transfers in my VitalPBX system using a Grandstream FXS gateway HT813. When I dial *2 to initiate an attended transfer, the original call is put on hold, I get a dial tone, and I can dial the destination extension. However, if the destination extension doesn’t answer, I can’t return to the original call.

I tried using the ## code to cancel the transfer, but it doesn’t seem to work. I’d like to know:

  1. Is ## the correct default code to cancel an attended transfer in VitalPBX? If not, what is the correct code?
  2. Are there any specific settings in VitalPBX or the Grandstream gateway that I should check to ensure the transfer cancellation works?
  3. Is it possible to configure a custom behavior, such as a timeout to automatically return to the original call if the destination extension doesn’t answer? If so, how can I implement this in the Dialplan or another section of VitalPBX?

Environment Details:

  • VitalPBX Version: 4.5.1-1
  • Gateway Model: HT813
  • Phone: Analog phone connected to the FXS port
  • DTMF Method: Configured as RFC2833 (default)
  • Observed Behavior: After dialing *2 and the extension, if the extension doesn’t answer, the ## code doesn’t return to the original call, and I don’t know how to recover it.

Any help or suggestions on how to configure transfer cancellation or implement a timeout in the Dialplan would be greatly appreciated. If needed, I can provide logs from VitalPBX or the gateway for troubleshooting.

Thanks in advance!