Ok, you have two trunks locked together.
The next step is to find out what is transferring one trunk to another. Is it supposed to?
There are several ways to fix this, all depending on what device is transferring trunk to trunk and if that is supposed to happen.
Go into your SMDR form and be sure you have smdr turned on.
Then go into the COS of the trunk and be sure it is turned on in there also.
Then when it happens next busy the PLID and RTS the PLID.
Command "busy <PLID>" , then "force";
This will disconnect the call.
Then restore the trunk "rts <PLID>"
If SMDR was active BEFORE the call, you can do a search for the call to see if you can find what device transferred the trunk to the other trunk.
My next question is this: are you a dealer or end user? The reason I ask is if you are an end user, I could probably knock this out in just a few minutes once I had remote access to your sytem. You'd have to go through the company I work for but that shouldn't be a big deal.
Ralph