Data Conversion Error: Value of Type Binary Cannot be Converted to Type Record

Expression.Error: Incompatible Types - Unable to convert Binary to Record. The provided value [Binary] cannot be transformed into the expected type [Type].

My code is:

---------------------------------

let

Credentials = "Username:Password",
AuthKey = "Basic " & Binary.ToText(Text.ToBinary(Credentials), BinaryEncoding.Base64),
url = "https://xxxxxxxxxxxxxxxxxxxxx.io/api/v1/product_bundle_index",
headers = [
#"Authorization"=AuthKey,
#"Content-Type" = "application/x-www-form-urlencoded",
#"Accept" = "application/json"
],
//postData = "{""order_id"":""[11931]""}",
record = [order_id = "11931"],
postData = Json.FromValue(record),
response = Json.Document(Web.Contents(url, postData))

in
// jsonResponse
response