We received a couple of similar cases about the 940 tax that's still showing as overdue. Our Payroll Team is already checking what's causing the Federal Unemployment to show as unpaid even if the forms and payments were already submitted.
In the meantime, please click Create Payment to remove the amount due. QuickBooks Online will automatically recalculate and update the system to reflect that nothing is due.
Let me know if you need anything else. The Community is always here to help you.