Custom Connector OAuth2 Scheduled Refresh Issue

I managed to make it work, it was a problem in one of my functions (I will check if I remember which one)
And I can confirm that Custom Connectors do refresh through the Gateway (no need to be the personal one).

EDIT: Found it. I implemented a logic developed by Matt Mason in the TokenMethod function. After this change, it worked.

TokenMethod = (grantType, code) =>
      let
                query = [
                           grant_type = grantType,
                           client_id = client_id,
                           client_secret = client_secret,
                           redirect_uri = redirect_uri
                             ],

// Code from Matt Mason. Check https://www.mattmasson.com/
                  queryWithCode = if (grantType = "refresh_token") then [ refresh_token = code ] else [code = code],

                  response = Web.Contents(token_uri, [
                  Content = Text.ToBinary(Uri.BuildQueryString(query & queryWithCode)),
                  Headers=[#"Content-type" = "application/x-www-form-urlencoded",#"Accept" = "application/json"],                      ManualStatusHandling = {400}]),
                  body = Json.Document(response),
                  result = if (Record.HasFields(body, {"error", "error_description"}))

                               then error Error.Record(body[error], body[error_description], body)
                              else body
      in
                  result;

Refresh = (resourceUrl, refresh_token) => TokenMethod("refresh_token", refresh_token);