If forgot the username and password, please do the following for resetting. 

1. Power off the switch and remove the top cover from the unit chassis.

2. Short the jumper labeled Default Password on the switch's mainboard.

3. Power on the switch. When you power the switch on, the following message appears on the LCD display:

    USERNAME AND PASSWORD INFORMATION HAS BEEN CLEARED. PLEASE POWER OFF THE SWITCH, REMOVE THE JUMPER, CLOSE THE CASE, THEN RESTART.

If the reset doesn't work, the unit may be bad. Please contact the original seller for RMA.