HELP: Nokia 3650 microphone doesn't work

I recently bought a Nokia 3650. The microphone does not seem to work without a headset. I have gone thru most of the settings and can't get it to work. The phone was primarily used with a bluetooth before I bought it. Does anyone have suggestions of any tell-tell signs to determine if the cell microphone is faulty OR if I have not checked a certain setting? Thanks.

Open the phone, make sure microphone is there. Clean contacts as microphone is not soldered. If this doesn't work, I would assume the mic is bad. Call Nokia and they will refer you to a local service center. There could be other things not making the mic work, e.g. water damage.

I will do that. The guy I bought it with used a bluetooth headset with it and used the internet on the phone. Would there be any setting that needs to be deactivated or activated ? Thanks.

Is the bluetooth icon "active" on the screen? If it is turn it off.