DTCs P225E00 & P20EE00 via Orbit,

[mmati8]

Hi everyone,
I’m looking for some advice regarding my Volvo D4 FWD, 2.0 190PS, 2019, 174.000KM
l scanned the car using Orbit and got these two active fault codes in the ECM:

• P225E00 – NOx Sensor Performance - Signal Stuck High Bank 1 Sensor 2
  
• P20EE00 – SCR NOx Catalyst Efficiency Below Threshold (Bank 1)
  

Timeline & Symptoms:

• 3,000 km ago: After a long, fast highway trip driving at 160-170 km/h, I first noticed a gray ash/soot buildup on the exhaust tips.
  
• Today: While driving, I got a Check Engine light, noticed a strong, distinct ammonia/urea (AdBlue) smell from the exhaust, and saw a significant puff of gray smoke under acceleration (which later disappeared).
  

My questions:

1. Does this diagnostics via Orbit point directly to a failing rear NOx sensor (Sensor 2) that needs to be replaced, or could this be a secondary consequence of something else, like a clogged DPF or a failing SCR catalyst?
   
2. Is there anything else I should check, reset, or perform in Orbit regarding these codes before or after replacing the sensor?
   

Any insights or similar experiences would be greatly appreciated! Thanks in advance.

Thnx,
Mati