Locking and encryption together = lost data.

[Occabot]

Locking an entry with a word or passphrase prevents an entry from being edited. After unlocking the entry, and then encrypting it, you can no longer decrypt that entry, even if you click unlock and use your encryption word or passphrase. And the "decrypt" option is no longer available.

Maybe you can fix the lock/unlock, because it does something to the encryption where you can never decrypt that entry again, and that is the same as losing data.