public async Task <ActionResult> SignInExternal(SaveTemporaryEmailAccountCommand command)
        {
            await _mediator.Send(command);

            var oAuth2AuthRequest = OAuth2Helper.CreateRequest(command.Email, command.UserId,
                                                               $"{Request.GetBaseUrl()}{Url.Action("LandingExternal")}", M365Helper.EmailScopes);

            return(View(oAuth2AuthRequest));
        }