Anything in the owners manual about it? Some of our big trucks have a button to force a re-gen, the ones that don't need the laptop hooked up to force one. If you don't have a re-gen button maybe there is a procedure for pushing a combo of buttons ie cruise or if it has a Diagnose function button. If not it's off to the dealer.

Idling is death on DPF's. If you are playing in the artic, Webasto diesel fired engine and cab heaters are worth their weight in gold. We did a wind turbine project a couple years ago at Diavek diamond mines. All kinds of trouble crossing the ice road at 25 MPH and it couldn't make enough heat to pull off a re-gen.

Kevin