Web Content Service Principle Authentication issue

Hi,

i'm trying to authenticate with a Azure Data Lake via M Query. I would do via the official connector but i didn't find a way to parametrize my credentials so i ended up here. 

I want to set the url/guids via parameters with as script in the Power BI Service (app.powerbi.com). I have these queries:

AccessToken as a function:

let
    GetAccessToken = () =>
    let
        tenantId = TenantID,
        tokenEndpoint = "https://login.microsoftonline.com/",

        // Create the body for the token request
        tokenBody = [
            client_id = ServicePrincipleClientID,
            client_secret = ServicePrincipleClientSecret,
            scope = "https://storage.azure.com/.default",
            grant_type = "client_credentials"
        ],

        tokenRequest = Web.Contents(tokenEndpoint, [
            Content = Text.ToBinary(Uri.BuildQueryString(tokenBody)),
            Headers = [#"Content-Type" = "application/x-www-form-urlencoded"],
            //Timeout=#duration(0, 0, 0, 2),
            RelativePath = TenantID & "/oauth2/v2.0/token"
        ]),

        source = tokenRequest,
        tokenSource = Json.Document(tokenRequest),
        result = tokenSource[access_token]
    in
        result
in
    GetAccessToken

Data Query:

let 
    accessToken = GetAccessToken,
    UtcTimeZone = DateTimeZone.UtcNow(),
    UtcTime = DateTimeZone.RemoveZone(UtcTimeZone),
    UtcTimeText = DateTime.ToText(UtcTime, [Format="r"]),
    headers = [
            #"x-ms-version" = "2023-08-03",
            #"x-ms-date" = UtcTimeText,
            #"Authorization" = "Bearer " & accessToken
        ],
    response = Web.Contents (DataLakeUrl, [
        Headers = headers,
        RelativePath = ConsumableStorage&ConsumableFileName
        ]),
    source = Text.FromBinary(response)
in 
    source

The thing is, the data will load and show in report and after refresh locally, it won't show any errors. When i upload those reports to the Power BI Service, it won't connect an throw this error: 

"400): Value for one of the query parameters specified in the request URI is invalid." 

On refresh in PBI Service, i get this error: [Unable to combine data] Section1/DataSource/source references other queries or steps, so it may not directly access a data source. Please rebuild this data combination.. The exception was raised by the IDbCommand interface.

The thing is, we use hierarchical namespace (dfs) and not blob, but i could access the files via Postman and also locally with my M Query.

I would be really thankful for any idea! 🙂