Hi Phonchai Sakunchinnasee,
Good day to you.
We have checked your reported problem at our end. For your case, our component max value set on DatePicker component, but we were unable to identify the exact root cause of this problem. So, could you please share the below details?
a. Screenshot of your problem for both client and server machine.
b. Component rendering code block
c. Syncfusion package version details
d. If possible, replicate your problem with sample.
Meanwhile, we are ready to assist and resolve your problem in lively. So please let us know your convenient time for web meeting. We will make every effort to have this meeting scheduled on a date and time of your convenience.