P0344 Chrysler -

Question

I have had this code come on me three time so far, the first time I got the code I bought a new sensor the second time I cleaned excess oil that was on the sensor down to the wires, and that helped for about two month but now just a couple of days ago I got it again so what can be the problem, and its only been about a 1yr since I brought the new Sensor. and the 2nd and third time code just recently took place this summer.