public async Task Subscribe(CancellationToken stoppingToken)
 {
     await _eventStoreClient.SubscribeToAllAsync(
         await _streamManager.GetPosition(),
         async (subscription, @event, cancellationToken) =>
     {
         _logger.LogInformation("EventAppeared at position: {arg2}", @event.OriginalPosition?.CommitPosition);
         await _streamHandler.Handle(@event.Event);
         await _streamManager.SetPosition(@event.Event.Position);
     },
         filterOptions : new SubscriptionFilterOptions(
             StreamFilter.Prefix("Identity")
             ),
         cancellationToken : stoppingToken
         );
 }