iOS SpeechSynthesisUtterance can not set language

I have SpeechSynthesisUtterance working in my native language (English) but I need to set the language to Italian.

The code works correctly in Mac Safari but in iOS Safari tyhe pronunciation is English not Italian.

An easy test is the Italian: "Ho i soldi", "h"is silent in Italian.

Here is my code:

function speak(text) {

var speech = new SpeechSynthesisUtterance();

speech.text = text;

speech.rate = parseFloat(rateInput.value);

speech.lang = 'it';

speech.voice = speechSynthesis.getVoices().filter(function(voice) { return voice.name == 'Luca'; })[0];

window.speechSynthesis.speak(speech);

}

I have downloaded Italian "Luca" and have set it as the Default.