Hi Kunal Bagga,
I am not sure what your exact implementation is, but I suppose that you have faced an issue that has been already explained in this help article
. Please make sure that you have defined the RadPanelBar structure as is described there.
In case the issue persists - could you please paste here the markup of the RadPanelBar that you have defined?
(Your code will be nicely formatted and readable if you use the "Format Code" tool
All the best,
the Telerik team
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