Need some suggestion on why P0170 error code

[alpac]

I got the check engine light on since yesterday. Not sure if it is related or not but I filled the tank about 30mns and 75 miles before that happened. The code error code I get is P0170 which gives "The PCM has determined that during testing, the fuel compensation value for bank 1 exceeded the specified range- Possible causes MAF, Oxygen sensor, Ignition misfire, Fuel Injector problem".

It cannot be the ignition misfire as the engine works perfectly. Did not notice any significant change in the fuel consumption either. I am thinking o2sensor but before changing it I am wondering if it could not be a bad gas. Anyway I will clear the code and see if it comes back.
Any suggestion about what the cause could be is welcome.
Thanks