Hello everyone, I have had my corsa since Dec 2019, it is on 63k miles and is a 2011 sxi 5dr. I have had the engine management light come on and it reads the p0420 code which is “catalyst system efficiency below threshold bank 1” I have also noticed that my fuel consumption has gone up. I usually fill up every 3/4 weeks but have filled up 3 times in July. Can some suggest what the issue could be? Could it be the oxygen sensor or is my cat bust. Please help me out! Thank you.