API call with JSON formatted body

Hello,

I am looking for a little help with regards to an API call I am trying to make and I cannot quite get it to work.

let

    AccessToken="Bearer "&GetAuthToken(),

    url="https://gateway.qg2.apps.qualys.eu/rest/2.0/search/am/asset",

    body = "
        {
            ""filters"":
            [
                {
                ""field"":""software.name"",
                ""operator"":""contains"",
                ""value"":""Chrome""
                }
            ]
        }",

    headers=[#"Content-Type"="application/json",#"X-Requested-With"="PowerBi",#"Accept"="*/*",Authorization=AccessToken],

    Source = Web.Contents(url,[Content=Text.ToBinary(body),Headers=headers,Query=[#"includeFields"="hardware"]]),

If I use powershell, I can get this to work using a similar format. 

#Create our search criteria.
$body = @"
{
    "filters": [
    {
    "field": "software.name",
    "operator": "CONTAINS",
    "value": "Chrome"
    }
    ]
   }
"@

#Now we will go and get the first set of records
$headers = New-Object "System.Collections.Generic.Dictionary[[String],[String]]"
$headers.Add("X-Requested-With", "Postman")
$headers.Add("Content-Type", "application/json")
$headers.Add("Accept", "*/*")
$headers.Add("Authorization", "Bearer "+ $authtoken)

$response = Invoke-RestMethod 'https://gateway.qg2.apps.qualys.eu/rest/2.0/search/am/asset?includeFields=hardware' -Method 'POST' -Headers $headers -Body $body

I suspect I have done something silly or made a typo, but I just cannot get this to work in PowerBi. I keep getting a http 400 error.

DataSource.Error: Web.Contents failed to get contents from 'https://gateway.qg2.apps.qualys.eu/rest/2.0/search/am/asset?includeFields=hardware' (400): Bad Request
Details:
DataSourceKind=Web
DataSourcePath=https://gateway.qg2.apps.qualys.eu/rest/2.0/search/am/asset
Url=https://gateway.qg2.apps.qualys.eu/rest/2.0/search/am/asset?includeFields=hardware

Any insight would be hugely appreciated.

Thanks

John