Hi Nirmal Kumar Boopalan,
In case the SelectionStart and SelectionEnd properties of the RadTimeBar control are bound, please make sure that you are using two-way binding. Additionally, please note that there is a required precedence, when setting the properties of the control. You can read more about this in our online documentation.
In case the problem persists, please open a formal support ticket and send us a running project, demonstrating the problem that you have.
the Telerik team