Shoutbox

I chose locking my record by setting up password before and now I would like to stop setting up the password and keep my record unlock for the future.

However, what can I do in order to unlock the record before, which is locked at the moment?

By 'record', I'm guessing chat logs? you can 'unlock' or decrypt current logs permanently with the information here:
Encrypting, decrypting etc. of Plus! chatlogs

As for stopping the encryption,
Plus Preferences > Conversations > Logs Encryption > uncheck the box to protect logs