Dynamic Data Source Error in Power Query

I'm getting Dynamic Data Source error in Power Query as below :
"Some data sources may not be listed because of hand-authored query"

and below is my code; How should I modify it?

let
BaseUrl = "https://yourdomain.udemy.com/api-2.0/organizations/224484/analytics/user-course-activity/",
EntitiesPerPage = 100,

GetJson = (Url) =>
let Options = [Headers=[ #"Authorization" = "Token"]],
RawData = Web.Contents(Url, Options),
Json = Json.Document(RawData)
in Json,

GetEntityCount = () =>
let Url = BaseUrl,
Json = GetJson(Url),
Count = Json[#"count"]
in Count,

GetPage = (Index) =>
let Page = "?&page=" & Text.From(Index),
Page_Size = "&page_size=100",
Url = BaseUrl & Page & Page_Size,
Json = GetJson(Url),
Value = Json[#"results"]
in Value,

EntityCount = List.Max({ EntitiesPerPage, GetEntityCount() }),
PageCount = Number.RoundUp(EntityCount / EntitiesPerPage),
PageIndices = {1 .. PageCount},
Pages = List.Transform(PageIndices, each GetPage(_)),
Entities = List.Union(Pages),
Table = Table.FromList(Entities, Splitter.SplitByNothing(), null, null, ExtraValues.Error),