Emailed voicemails arriving as .WAV when I need.wav

I have searched and read, and searched some more. I can’t figure out how to change the email attachment from a WAV to a .wav. Apparently it makes a difference. Sorry for being a newb, but I did try searching.

Look in the “format” section.

edit /etc/asterisk/voicemail.conf

; 1st listed format gets emailed
format = wav ; for voicemail try to send better quality wav file

for email:
edit /etc/asterisk/