The returned structured data is an array of objects, so you most likely need to specify on which entry you want to change the brand tag:
Something like this:
structuredData[1]["brand"] = "Black+Decker";
In order to know what the structured data looks like, you should add console.log(structuredData) to inspect the returned object:
async function initBrand(){
let structuredData = wixSeo.structuredData;
console.log('structuredData); // inspect structuredData
// change structuredData here
await wixSeo.setStructuredData(structuredData);
}
I also noticed that you have a number of errors in your code:
It is incorrect to have more than one onReady() function. You should delete the first empty one.
You are calling an initReview() function that does not exist, and you are not calling initBrand().
