I can't understand why this is throwing that error when I am working inside async await functions... Not sure if makes a difference but I am executing this code inside the content script of a chrome extension

Thanks in advance!

const getFromStorage = async function(key) {
return new Promise((resolve, reject) => {
    chrome.storage.sync.get(key, resolve);
})
    .then(result => {
        if (key == null) return result;
        else return result[key];
    });
}

let updateArray = await getFromStorage("toSaveArray");