HTTP PUT call error to shopify when sending array in json request for metadata list type

This is an http PUT response to update the metafield of an existing article in shopify.

PUT API documentation on Articles

func UploadArticleListImg(client *http.Client, ArticleIDs []string, imageURL []string, blogID string) {

    newArticleQueryFinal := fmt.Sprintf(newArticleQuery, blogID)
  for _, ID := range ArticleIDs {

	Article := &ArticlePut{
		Blog_id: blogID,
		ID:      ID,
		Metafields: []ArticlePutMeta{
			{
				Key:       "flip_book_images",
				Value:     imageURL,
				Type:      "list.url",
				Namespace: "custom",
			},
		},
	}

	spew.Dump(Article)
	articleJSON, err := json.Marshal(map[string]interface{}{"Article": Article})
	articleReq, err := http.NewRequest("PUT", newArticleQueryFinal, bytes.NewReader(articleJSON))
	articleReq.Header.Add("X-Shopify-Access-Token", token)
	articleReq.Header.Add("Content-Type", "application/json")

	resp, err := client.Do(articleReq)
	if err != nil {
		fmt.Println(err)
	}
	fmt.Println(resp.Status)

	body, err := io.ReadAll(resp.Body)
	if err != nil {
		fmt.Println(err)
	}

	sb := string(body)
	fmt.Println(sb)

	}

}

my structs are like below

type ArticlePut struct {
	Blog_id    string           `json:"blog_id"`
	ID         string           `json:"id"`
	Metafields []ArticlePutMeta `json:"metafields"`
}

type ArticlePutMeta struct {
	Key       string   `json:"key"`
	Value     []string `json:"value"`
	Type      string   `json:"type"`
	Namespace string   `json:"namespace"`
}

im getting an error saying

> 406 Not Acceptable

These are my Article metafield definitions.

and this is the documentation on the list_url metadata type

what am i missing here?? Please help.

If I input the values for metafield like below it works.

Value: `["https://www.shopify.com","https://www.shopify.com","https://www.shopify.dev"]`

But I dont know how to construct the imageURL to have single quotes around