Custom Sound selection "Not an audio file"

[S7venLights]

I can't seem to set my WAV audio file as a notification:

[User@fedora battery-notify]$ battery-notify -s /var/home/User/Documents/Random/David_Charge_Notifications/Please_charge_me_David_Atenborough_No_Phone.wav
/var/home/User/Documents/Random/David_Charge_Notifications/Please_charge_me_David_Atenborough_No_Phone.wav is not an audio file