DD15 low NOx conversion efficiency and bad DEF Quality

Hi I'm having some major problems with 2012 Cascadia its been a nightmare truck. It has a low NOx conversion efficiency and bad quality DEF. The NOx outlet sensor have been charged and brand new DEF pump replaced.The dosers cleaned and inspected air supply checked,voltages check all of the wiring inspected. All of the temperatures pressure dosing quantity correct,the whole system removed from the truck and cleaned. Even a DEF tank flushed and refilled. It to the regen starts normally low PPM on the outlet 80% efficiency and then it slowly goes down to 0 and that's it,truck keep regen and it never stops. Any help would be appreciated thanks.

 

Filters have been pulled today and cleaned,all of the DOC pressure temperatures etc look normal according to a manual

 

Wires all correct and a brand new sensor,suspecting it's a failed complete SCR system unfortunately.

 

This is a exact name of code,however the DEF tank been removed and cleaned and DEF fluid replaced.