more details please. this is a technical support forum.
describe in detail the method you use to "transfer" the call (each button pressed)
each button pressed.
And the customer CID is "Used for Drop, After-hours and No-agent-no-queue actions." Is this a drop?
If the call is passing to the agent via a "carrier", it may be a good idea to use a carrier dialplan that does not include the "agi" line (make a special dialplan for this purpose, see if it helps).