Phone extension forwarded by ivr keeps ringing forever

I had installed FreePBX (Core, IVR I enabled IVR for my inbound route. Now my problem is when the incomming call is answered by an AVR and routed to selected extension and the caller hangs-up before the extension answered the call it KEEPS RINGING FOREVER. the extension won’t stop ringing until you hang-up it manually.

I use DIGIUM AEX2400 as my hardware. Is there a patch with this issue? Need help please… Thanks