API Authorization - Expression.Error: We cannot convert a value of type Record to type Text

Hi All,

I am having issues passing an Authorization token to a Dynamic Web Service URL in order to have it refresh in the Service. Trying to dynamically pull data from prior 30 days. API call works if all values are hardcoded.

Getting a "Expression.Error: We cannot convert a value of type Record to type Text" error. Appears to be issue with the Header but I can't figure out why.

let

    Source = Csv.Document(
                Web.Contents(#"Report URL Trunc",
                    [
                        RelativePath = #"Report URL 30 Offset",
                        Query =
                            [Headers=[#"Authorization" = "Bearer " & GetAccessToken()]
                            ]
                    ] 
                            ),
                    [Delimiter=","]),
        #"Promoted Headers" = Table.PromoteHeaders(Source, [PromoteAllScalars=true])
                   
in
    #"Promoted Headers"