HELP Please I'm lost 2009 2.2ltr diesel
 

AdBlue and diesel issues 2009 diesel 2.2ltr.
purchased vehicle sight unseen at a cheap price. Has been great but now having fuel issues.
Today the AdBlue gage said it was low (830kms) left. I put diesel in and travelled 100kms (I live in NT) down the road, DTE gage said there was 342kms remaining when I pulled up. Few hours later went to go down the road and now AdBlue says full and Diesel is empty, light on, and DTE says 40kms remaining... it also had less power today than usual too.
HELP!!!!!