The issue with Invoice Printed tags should now be resolved.
One thing to we must mention however is that the fix only applies to newly printed orders. Orders where invoices were printed while the issue was present might still not show the invoice printed tag, thus we advise you to process such orders. It can be checked in the Audit Trail of the order if the Invoice has been printed or not. Also, you can cross-compare the actual printed invoices against the orders in your Open Order screen. We do understand that this is not ideal and do apologies for the inconvenience this has caused.