Why have a load of journal entries dated 31/03/2019 appeared? They werent there last month and now it has confused all my customers

Hello there, @Marky.

You can view your journal entries and check the audit history who create the transactions.

In the meantime, you can delete a journal entry in QuickBooks Online by following the steps below:

1. Locate the Journal Entry you want to delete.
2. On the Journal Entry screen, click More at the bottom of the screen.
3. Select Delete and click Yes to the prompt.

Once the Journal Entry is deleted, you can no longer undo it. However, you can always open the Audit Log to check the details if you want to re-enter it. Here's how:

1. Go to the Gear icon and select Audit Log.
2. You can click Filter at the top of the table to locate the transaction easily, then click Apply.
3. Find one of the deleted entry, and click View under the History column to view the details.

To learn more about entering and modifying journal entries, check out this video tutorial: Journal entry.

Please let me know if you should have any questions and concerns. I'm always here to further assist. Have a great day!