I am not sure what exactly is causing the issue in the current implementation. Please take a look at the following documentation page, which demonstrates how to get started
with the Kendo UI DropDownList for ASP.NET MVC. The demo about cascading DropDownLists
may also be helpful.
If you are still experiencing any issues, please send me a small sample project, so I could inspect it locally and assist you further. I am looking forward to hearing from you.
All the best,
the Telerik team
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