Use Web.contents( ) with Query & RelativePath parameters for Json Data List in Power Query M

Hello,

I want to parametrize this URL using Relative Path and Query functions inside Custom M Function, here my URL and my code:

URL = "http://newapi.omni.com/1.13/Omni.svc/GetRelationListJson?json={TypeIDs: 10,ObjectID: "& property_id &",LanguageId: 2, CustomerName: CustName, CustomerPassword :Pass}"

property_id = Parameter used as Invoke Custom Function 

Source = (Property as number) as table =>

let
    property_id = Number.ToText(Property),
   

    Source = Json.Document(Web.Contents(URL_BODY,
   [RelativePath= "GetRelationListJson?json={TypeIDs: 10,ObjectID: "& property_id &",LanguageId: 2, CustomerName: CustName, CustomerPassword :Pass}"])),

......

This work only in Power BI Desktop, I have error in Power BI Service : [Unable to combine Data] ......

To fix this issue, I folowed CHRIS WEBB Blog, but unfortunately he didn't gave us an example with a json list.

I tried this, but it's not working: 

Source = Json.Document(Web.Contents(URL_BODY,
[RelativePath= "GetRelationListJson",
Query =
          [
            json=
                    {
                      TypeIDs= 1,
                      ObjectID= property_id,
                      LanguageId= 2,
                      CustomerName= "Cust",
                      CustomerPassword= "Pass"
                    }

            ]

Any idea on how to handle with list of Json inside Query function of URL please?

Thank's in advance for your help