p2002 is an old one,. there was an ecu upgrade to sort this out, sounds like you've done a bunch of short journeys and the dpf is felling clogged, the altered the pressure differential in the ecm to prevent getting this code unless there was a proper real problem.
You need to get it to attempt to regenerate, needs a bit of a run to get hot enough, also worth checking the correct engine oil has been used for servicing, as that can affect the dpf to.
I'm running as a taxi, this fault occured at 80k and was fixed by dealer (takes a 2 day trip to get there). as over 100k it is now out of warranty. Oil was checked and confimed ok at this time. there is no noticable difference in performance. Dealer suggested running at high revs to see if this would clear fault but made no difference