Please see below for steps to remove the journaling configuration in your Office 365 account.

Step 1 – Login to your Microsoft 365 Purview admin center using your Microsoft 365 admin account at:
https://compliance.microsoft.com
Select, the “Data lifecycle management” (1) to expand the menu, select the “Exchange (legacy) menu item (2), select the “Journal rules” settings on the top menu bar (3).

Step 2:
Select the journaling rule that you added for MessageWatcher (1), then select the “Delete” icon (2) to remove the rule. Click “Delete” when asked to confirm. This will stop the email journaling that was used for archiving your emails.