convert-audio function error

i deploying functions
i functions: ensuring necessary APIs are enabled...
✔ functions: all necessary APIs are enabled
i functions: preparing functions directory for uploading...

Error: Error occurred while parsing your function triggers.

TypeError: require(...) is not a function
at Object. (/Users/username/Firebase/functions/index.js:19:45)
at Module._compile (internal/modules/cjs/loader.js:1147:30)
at Object.Module._extensions..js (internal/modules/cjs/loader.js:1167:10)
at Module.load (internal/modules/cjs/loader.js:996:32)
at Function.Module._load (internal/modules/cjs/loader.js:896:14)
at Module.require (internal/modules/cjs/loader.js:1036:19)
at require (internal/modules/cjs/helpers.js:72:18)
at /usr/local/lib/node_modules/firebase-tools/lib/triggerParser.js:15:15
at Object. (/usr/local/lib/node_modules/firebase-tools/lib/triggerParser.js:53:3)
at Module._compile (internal/modules/cjs/loader.js:1147:30)

I am following the instructions provided and I am getting the error shown above.

Can you provide an idea on what could fix this issue?

Regards