Can u tell me what the problem of this code PO340

I have a 1999 BMW 740 il My SES light came on so I hooked up my OBD code reader p0340 - Camshaft Position Sensor Circuit Malfunction is what came up. so I went to the BMW parts department and bought the Camshaft Position Sensor.
I Replaced the with the new. My SES light was still on so I hooked up the OBD reader again hoping it may reset my SES light but it didn't what did happen is the OBD reader came up with the same code (p0340 - Camshaft Position Sensor Circuit Malfunction) witch is what I just replaced. now I'm at a loss. I'm not sure how to reset my SES light and if I just replaced the Camshaft Position Sensor why dose it the OBD code p0340 still come up. Any suggestions?

There is no one cause of this code. P0340 - Camshaft Position Sensor Circuit Malfunction

Possible causes - Harness or connectors (The sensor circuit is open or shorted)
- Camshaft position sensor may be faulty
- Camshaft (Intake) may be damage
- Starter motor may be faulty
- Starting system circuit
- Dead (Weak) battery Possible solution - Charge battery
- Repair harness or connector
- Replaced Camshaft Position Sensor.