REST with Bearer Token - Successfull refresh in advanced editor, failure in apply changes

Hello,

I need to invoke REST APIs with Bearer token authentication to retrieve the data for my model; same queries work in Postman.

I defined the following functions/queries in the Power BI advanced editor which are working fine in the advanced editor area, but when I close and try to apply the changes in my dashboard, the process is failing.

First of all, I defined a GetBearerToken function which returns my access_token.

let
    GetBearerToken = () =>
    let
        baseUrlToken = "BASIC URL",
        relativePathToken = "login",
        bodyToken = "grant_type=password&username=USER&password=PWD&client_id=CLIEND_ID&client_secret=CLIENT_SECRET",
        headersToken = [#"Content-Type"="application/x-www-form-urlencoded"],
        responseToken = Json.Document(Web.Contents(baseUrlToken, [RelativePath=relativePathToken, Headers=headersToken, Content=Text.ToBinary(bodyToken)])),
        accessToken = responseToken[access_token]
    in
        accessToken
in
    GetBearerToken

Then in my queries, I recall this one and I retrieve the data

let
    // Recupera il token
    accessToken = GetBearerToken(),

    // Funzione per recuperare una singola pagina
    GetPage = (PageNumber as number) =>
    let
        baseUrl = "BASE URL",
        relativePath = "RELATIVE PATH",
        query = [
            dql = "PARAMETER", // Modifica i campi qui
            page = Text.From(PageNumber)
        ],
        headers = [Authorization="Bearer " & accessToken],
        response = Json.Document(Web.Contents(baseUrl, [RelativePath=relativePath, Query=query, Headers=headers])),
        entries = response[entries],
        nextPage = if List.NonNullCount(List.Select(response[links], each _[rel] = "next")) > 0 then PageNumber + 1 else null,
        result = [Entries = entries, NextPage = nextPage]
    in
        result,

    // Recupera tutte le pagine
    GetAllPages = List.Generate(
        () => [PageNumber = 1, Results = GetPage(1)],
        each [Results][Entries] <> null and List.Count([Results][Entries]) > 0,
        each [PageNumber = [PageNumber] + 1, Results = GetPage([PageNumber] + 1)],
        each [Results][Entries]
    ),

    // Combina i risultati di tutte le pagine
    CombinedResults = List.Combine(List.Transform(GetAllPages, each _)),
    ResultTable = Table.FromList(CombinedResults, Splitter.SplitByNothing(), null, null, ExtraValues.Error),
    #"Expanded Column1" = Table.ExpandRecordColumn(ResultTable, "Column1", {"content"}, {"content"}),
    #"Expanded content" = Table.ExpandRecordColumn(#"Expanded Column1", "content", {"properties"}, {"properties"}),
....

Everything works great in the advanced editor preview area, but when I click on "Close & Apply Changes", all the functions give an error, even the GetBearerToken. The error is the same for all the executions, an example from the GetBearerToken and the one reported above:

GetBearerToken
Failed to save modifications to the server. Error returned: 'OLE DB or ODBC error: [Expression.Error] The field 'entries' of the record wasn't found.. OLE DB or ODBC error: Exception from HRESULT: 0x80040E4E. The current operation was cancelled because another operation in the transaction failed. OLE DB or ODBC error: Exception from HRESULT: 0x80040E4E. OLE DB or ODBC error: Exception from HRESULT: 0x80040E4E. OLE DB or ODBC error: Exception from HRESULT: 0x80040E4E. OLE DB or ODBC error: Exception from HRESULT: 0x80040E4E. '.

I cleaned the cache but nothing.

Do you have any suggestions on this?

Thanks

Simone