how to reset vplex or remove the old configuration

when i  type  configuration system-reset ,it show:

VPlexcli:/> configuration system-reset                               
configuration:  Evaluation of < > failed.
cause:          Don't know how to process arguments "system-reset".

when i type configuration system-setup,it show:

next to next

Would you like to run the setup process now? [yes]:                
Starting the setup....

Setting up environment for certificate creation...
Certificates have already been configured.
Skipping the certificate creation.

Please enter the Local Webserver Host Certificate passphrase for setting up Java Key Store:                                               

Re-enter the passphrase for the Certificate Key:                

Please enter the Local Webserver Host Certificate passphrase for setting up Java Key Store:                                               

Re-enter the passphrase for the Certificate Key:                    
Passphrases did not match, please try again ( you have 2 tries left )

Please enter the Local Webserver Host Certificate passphrase for setting up Java Key Store:                                               

Re-enter the passphrase for the Certificate Key:                   

You must enter a value.

i do not konw what  is the key

please help me! thanks!