Toyota Repair: oxygen sensor, toyota camry v6, toyota camry

Question
I have a '99 Toyota camry V6 with 58 T mi on it. My check engine light came on and I had it scanned. The scan read oxygen sensor (Bank 1 Sensor 1) I had OS replaced and the light went out for 1 day and came on again. I had code cleared out and light came on again. I had it scanned again and it read OS. What else could be causing the light to come on in the car? Could the replacement oxygen sensor be bad?  

Answer
I'm not sure if I've already answered this question so this may be a duplicate answer, the bank one sensor one is located in the exhaust manifold near the firewall, it's possible that the wrong side was replaced, please find out from the shop that replaced the sensor which one they replaced, the one near the radiator or the one near the firewall and let me know.