Hi Hien ,
Thank you for contacting Telerik support.
Yes indeed the desired resize functionality in MonthView is a feature we have added last year so it is available only in the newer versions of Telerik controls as you can see in this online demo
. In such case in order to have them you will have to update with a newer version of the controls.
Hope this will explain the issue. If you have further questions please don't hesitate to contact us again.
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