Did they tell you what it is? If they didn't, it's a suspension preload motor end of travel fault. The service manual says disconnect the negative battery terminal connection for 2 minutes, reconnect it and turn the ignition on and wait for it to reinitialize which could take up to 60 seconds and then adjust the suspension with the electronic controls. If that fails, contact Triumph. I PRESUME since they are a dealer they did all that. No indication what Triumph's solution would be. I would bet member Digital has a better handle on a solution than I could ever imagine.