Hello Andy Zhang,
Please provide a screen shot of the device manager when the board is connected. Also, go to properties of the enumerated device and check the error reported.
Looks like issue with the schematics.
Please refer to this KBA: USB-Serial: Hardware Design Schematic Checklist - KBA231249 and make sure all the points are met.
The Reset pin should not be left floating. Please pull up the pin to VDDD using a suitable resistor.
Please let me know if you still face the same issue after correcting the schematic?