Solution of password forgetting when logging in to oracle database

What should we do if we forget our password when we log in to oracle via http://localhost: 1158/em?

Run sqlplus to enter the password input interface
User name input: connect as sysdba
Password: Just type here

Then enter the following command:
Change password command
alter user system identified by new password;
Log in immediately after success and find that you can't log in. Prompt that the user name is locked, so re-enter and run the following code to unlock

alter user myuser account unlock;