POST local storage - angular

[railcats]

I'm trying to POST my local storage to an API, but everytime I do it, I get a status: 400. Title of error says '"One or more validation errors occurred."'

I must be doing this wrong. I'm trying to loop through all the key value pairs and then send that via a POST.

public postInfo() {
for (let i = 0; i < localStorage.length; i++) {
const key = localStorage.key(i);

const headerDict = {
'Content-Type': 'application/json',
'Accept': 'application/json',
'Access-Control-Allow-Headers': 'Content-Type',
}

const requestOptions = {
headers: new HttpHeaders(headerDict),
};

this.http.post(this.url, key, requestOptions).subscribe(data => {
console.log(data);
});
}

}
Also here is how I'm saving my local storage:

addToCart(product: Product) {
var sendJson = JSON.stringify(product.productID);
var jsonData = JSON.stringify(product.productName)
localStorage.setItem(sendJson, jsonData);
}