Hi everyone

I have a 2012 micra in with p0133 o2 sensor circuit bank I sensor 1 and mil on and a slight hesitation when accelerating. In live data the sensor 1 is mentioned as equivalence ratio and at 3.000rpm it shows 1.00 which is the same as a saved previous live data of the same car. sensor 2 also is the same. The only difference between the previous and the current live data is the fuel trims are now about 12% and before it was 6% also the spark plugs are a bit sooty. does it look to you that there is a slight air leak and to compensate it's over fueling?