how to recover login password of web on ar6121c-s

the parameter settings are as follows on putty:

Bits per second: 9600
Data bits: 8
Parity: None
Stop bits: 1
Flow control: None

reboot——Ctrl+B——input password: Admin@huawei——Password Manager——Clear the console login password

<Huawei> system-view
[Huawei] user-interface console 0
[Huawei-ui-console0] authentication-mode password
[Huawei-ui-console0] set authentication password cipher
Enter Password(<8-128>):
Confirm password:
[Huawei-ui-console0] return
[Huawei] aaa
[Huawei-aaa] local-user chenshi password irreversible-cipher chenshi.de
[Huawei-aaa] local-user chenshi service-type http
[Huawei-aaa] local-user chenshi privilege level 15
[Huawei-aaa] return
<Huawei> save