I got a service emissions light no my dashboard and I checked it with the cpu and I got code P0135 and I replaced the O2 sensor on bank 1 and I still get that code after the car was running without it for about 3 days. Can anyone help me out?

Did you clear the code?

An oxy sensor code will set if that bank is either running too rich or too lean. Codes never tell you what to replace! They localize the problem so you can follow a logical diagnosis.