Hi Rudy,

I already updated the code like the below:

// The second and millisecond values can't be selected by picker.
// So set these values as same as
// the current value of datetime/datetime-local input field
// when currentDatetimeValue is not equal to ''(space),
// or set the values as same as current time.
if (currentDatetimeValue !== '') {
  date = new Date(this._currentDatetimeValue);
} else {
  date = new Date();
}
second = date.getSeconds();
millisecond = date.getMilliseconds();

Thanks. :)