Retrieve password after rotate-root

I am trying out the database secret engine.

I created “database/config/mysql” with a simple username “vault” and password “vault”.

Then I use rotate-root to change the password of user “vault”.

Now, if I want to reuse the user “vault” to create another config “database/config/mysql2”, how can I reuse the user “vault”? I no longer have access to its password.

Or should I create a new user on my mysql server for another config?