How do i tag a CIS refund, made by client ?

Hi,

I done works for a client and they incorrectly deducted CIS from the gross amount of the invoice.
I had reverse VAT on the invoice, they just never picked up on this and it meant I overpaid on my CIS for that invoice.

I declared the CIS for the amount they paid (under the instruction of my accountant) so I could close my monthly CIS deductions.
My client then spoke to their accountant and realised their error and refunded me the difference to the company bank account.
The next CIS period, I submitted my CIS amount minus the refunded amount so that the CIS paid from this client for all the works involved marry in with HMRC (under the instruction of my accountant).

The problem I have is, I don’t know how to tag this refund.
With the CIS being amended to suit with HMRC now and the invoice being marked as paid from the original payment, I’m at a loss of how to correctly log the CIS and refund in QF.

Anyone any ideas?

Thanks