the sendAudio function set wrong parameters, according to whatsapp business cloud api
the audio must not have an caption parameters,
if you set the param, it will return this error:
[{"status":"failed","message":"(#100) Unexpected key \"caption\" on param \"audio\".","type":"OAuthException","code":100,"fbtrace_id":"doe"}]
the sendAudio function set wrong parameters, according to whatsapp business cloud api the audio must not have an caption parameters, if you set the param, it will return this error: [{"status":"failed","message":"(#100) Unexpected key \"caption\" on param \"audio\".","type":"OAuthException","code":100,"fbtrace_id":"doe"}]