Invoke url does not send valid json

Invoke url does not send valid json

Hi!

I'm having a script sending a http post action to a third party software when a new record is created. 

The response I get is "error deserializing json" as if the code is not valid json. 

The simple code I'm sending is: {"Customer":{"Name":"Sven Eriksson"}}

I have tried the code in another service and it works fine. I can't understand why it doesn't work in Creator. 

Here is my code (I have masked access-token and client-secret):

header_data = Map(); header_data.put("Access-Token","xxxxxxxxxxxxxxxx"); header_data.put("Client-Secret","xxxxxxxxxxxxx"); header_data.put("Content-Type","application/json"); header_data.put("Accept","application/json"); namn = Map({"Name":"Sven Eriksson"}); parameter_data = Map({"Customer":namn}); url = "https://api.fortnox.se/3/customers"; response = invokeurl [ url :url type :POST parameters:parameter_data headers:header_data ]; info "Svar"; info response; info parameter_data;