I don’t know where it is located on your vehicle, but “sensor 2” means it is a sensor downstream of the cat. Sensor 1 is the sensor before the cat, usually sensor 1 is near the exhaust manifold. So look for a sensor with wires connected to it on an exhaust pipe downstream of the cat, or on the cat itself. You may have to remove heat shield(s) in various places to locate it. Be sure you are looking on the correct bank, if your car sports more than one cat.
And remember there’s often something that looks like a cat in the exhaust system – the resonator – but that part isn’t the cat.