Solution
This issue happen when Browser Access in Web Server only granted viewing.
To allow client have controlling privilege, you may go to Tools >> Options >> Web Server >> Browser Access, configure browser address as Allow viewing and controlling.

If you are using a LabVIEW Remote Front Panel connection through an executable (EXE) as a server, make sure the EXE’s INI file (e.g., MyApp.ini) includes the following configuration:
WebServer.TcpAccess="c+<your_client_ip>"
For multiple client IP addresses, use:
WebServer.TcpAccess="c+10.155.6.27;c+10.155.14.53"
To allow access from all IP addresses (not recommended for security reasons), use:
WebServer.TcpAccess="c+*"