SIP2SIP

I need to offer one or two callers the opportunity to leave voicemails if I cannot take the call in person. Over the last couple of days, I have made two test calls. In both instances the system stopped ringing the destination number as I would have expected, but the originating caller continues to get ring tone until the originating network decides that it has tried for long enough and clears the call attempt down. Ringing 1233 from the destination phone to collect voicemails etc just goes silent and then displays "408 time out".

I wonder if you could investigate and correct, please.

Many thanks for your efforts,

Jeff