Hi Ashok,
2 points you need to check.
1. Debug in the Genil class method which will change the data and check whether the new data is set to buffer or its not updating due to some condition checks failed.
2.Check whether the buffer is cleared or not every time you change some data. Until the buffer is cleared, the Read methods will not be called and so you can't see the updated data other than the first buffered data.
Hope this will help
Jayasri