[Tantrik ZX3]

Ok I have been gettting this code on my car for the few weeks.P1406 - DPF EGR Sensor Downstream Hose Off or Plugged While driving as well as P0420 - Catalyst System Efficiency Below Threshold (Bank 1). They both come on together every time. Now I changed the DPFE and both hoses and rest the light about a week ago and the check engine light keeps coming on and it is the same 2 codes. I'm really lost here and my car is running like a bag of crap so if anyone can help it would be great

Thanks Brad