What is prosopagnosia?

Facial recognition. Inability to recognize faces. Usually occurs with damage or deficit of the fusiform gyrus in the temporal lobe.
Facial Recognition. This is a rare phenomena, can be seen in temporal lobe seizures or personality disorders or abnormalities in the sedes of the brain from several causes to include focal lesions, some medications, illicit substances, or could be a normal phenomena upon awakening or dozing off at night (if temporary). Consult neurology.
Prosopagnosia. Prosopagnosia is a disorder that involved not recognizing faces, but being able to recognize voices, as you have indicated. The patient needs to immediately be evaluated by a neurologist to confirm or refute this.