2005 Malibu security problems

[pcstac]

I have a 2005 Malibu base model four door sedan. It is the passkey 3. I lost the ignition key so I bought one off ebay. I installed it and the security light would flash on the dashboard instrument panel when I turn the Ignition on. Also the alarm will sound for a minute or so and then shut off. The car starts then shuts off in about five seconds. I did the 30 minute relearn procedure. The light went off after the 10 minute wait each time but came back on after I tried to start the car. Now when I try to do the 30 minute relearn procedure again the light won't go off after the 10 minute wait. I did the thing where you hold down the door lock on the door panel and turn the switch on and off and it did lock the doors. It won't let me do that again either. After doing all that I decided to buy a door lock & key off ebay. It is from a different car than the Ignition switch. I installed it. Now when the alarm sounds I use the key and unlock the door and the alarm will shut off. Now after Installing the door lock & key, "with the Ignition switch off" the security light is solid for about 30 seconds after unlocking the door then it starts flashing. "With the Ignition switch on" it stays solid not flashing. The car starts then shuts off in about five seconds. Also I am locked out of the radio security settings. I don't know what else to do. If anyone could help me It sure would be appreciated. Thanks.