Delphi Windows Service 'running' but without action

I am trying to create a very simple Windows service. It runs fine (ie, beeps, logs) in debugging (console), and it installs fine and shows 'running' from Services however nothing is actually happening. Service Stops fine when requested. Same behaviour on alternative machines.

Project file:

PROGRAM ServiceProject;
{$ifdef DEBUG}
{$APPTYPE CONSOLE}
{$endif}

USES
  Vcl.SvcMgr,
  ServiceUnit IN 'ServiceUnit.pas', System.SysUtils{TestingService: TService};

{$R *.RES}

BEGIN

{$IFDEF DEBUG}
  TRY
    //In debug mode the server acts as a console application.
    WriteLn('MyServiceApp DEBUG mode. Press enter to exit.');
    //Create the TService descendant manually.
    TestingService := TTestingService.Create(NIL);
    //Simulate service start.
    TestingService.ServiceExecute(TestingService);
    //Keep the console box running (ServerContainer1 code runs in the background)
    ReadLn;
    //On exit, destroy the service object.
    FreeAndNil(TestingService);
  EXCEPT
    ON E: Exception DO
      BEGIN
        WriteLn(E.ClassName, ': ', E.Message);
        WriteLn('Press enter to exit.');
        ReadLn;
      END;
  END;
{$ELSE}
  //Run as a true windows service (release).
  IF NOT Application.DelayInitialize OR Application.Installing THEN
    Application.Initialize;
  Application.CreateForm(TTestingService, TestingService);
  Application.Run;
{$ENDIF}

END.

Select allOpen in new window

ServiceUnit:

UNIT ServiceUnit;

INTERFACE

  USES
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Classes, Vcl.Graphics, Vcl.Controls, Vcl.SvcMgr, Vcl.Dialogs;

  TYPE
    TTestingService = CLASS(TService)
      PRIVATE
        {Private declarations}
      PUBLIC
        FUNCTION GetServiceController: TServiceController; OVERRIDE;
        PROCEDURE ServiceExecute(Sender: TService);
        {Public declarations}
    END;

  VAR
    TestingService: TTestingService;

IMPLEMENTATION

{$R *.dfm}

  PROCEDURE ServiceController(CtrlCode: DWord); STDCALL;
    BEGIN
      TestingService.Controller(CtrlCode);
    END;

  FUNCTION TTestingService.GetServiceController: TServiceController;
    BEGIN
      Result := ServiceController;
    END;

  PROCEDURE TTestingService.ServiceExecute(Sender: TService);
    CONST
      SecBetweenRuns = 5;
    VAR
      Count: Integer;
    BEGIN
      LogMessage(datetimetostr(Now()) + ' : ServiceExecute', EVENTLOG_INFORMATION_TYPE, 0, 2);
      Count := 0;
      WHILE NOT Terminated DO
        BEGIN
          Inc(Count);
          IF Count >= SecBetweenRuns THEN
            BEGIN
              Count := 0;
              beep;
              LogMessage(datetimetostr(Now()) + ' : WHILE NOT Terminated DO', EVENTLOG_INFORMATION_TYPE, 0, 2);
            END;
          Sleep(1000);
        END;
    END;

END.

Select allOpen in new window

The Service /install fine as Administrator, going to Services the service starts and shows 'running'.. but no beeps, no Event Log. Service stops fine when requested.

What am I doing wrong?

Many thanks

Delphi 10 Seattle 64
Windows 10 Home 64
Windows 2016 Server 64