Hi Chandra,
Thank you for using Syncfusion products.
I am afraid that I am not able to reproduce the issue of 'Chart is not updated with new data at runtime'. I have created a test sample on this. Please refer the sample below and let me know if you could reproduce this issue.
http://websamples.syncfusion.com/samples/Chart.Web/6.2.0.40/P43019/main.htmPlease let me know if you require any more details.
Regards,
Jaya