What's wrong with this? Why is this not speaking?

Question

https://code.sololearn.com/WlP6XwORy8f5/?ref=app

Answer 1

Uncaught ReferenceError: SpeechSynthesisUtterance is not defined

://You can see the error in console.

Answer 2

That is not the problem. That erorr occurs everytime but inspite of that it speaks. But in this, it is not speaking.