Hey, I need to delete a credit not I entered incorrectly. Because it’s part of a paid tax period it’s throwing an error. I added it retrospectively

I turnes out its a bug in the message not the warning. Please do the following.
Go to the vat return for that period you'll find it in tax/
Click on the vat return and mark as unpaid
Delete the credit note and make your changes.
Go back to the vat return and mark as Paid.

That's it
Thanks Pete