When a journal is opened, and you then journal another report or data table, the second report or data table is added to the end of the open journal.
To prevent modifications to a journal, right-click the blank area at the bottom of the journal and select Lock. Additional reports are not added to the journal (as described in the following section). JMP instead finds an open unlocked journal or creates a new journal when you select the Edit > Journal command again.
To unlock the journal, right-click the blank area at the bottom of the journal and deselect Lock.