Right so I now need to raise an invoice for December in the way I would normally & then apply from credit?
Spot on! Once you’ve issued the invoice, you just use the log payment button to deduct the prepayment 
Right so I now need to raise an invoice for December in the way I would normally & then apply from credit?
Spot on! Once you’ve issued the invoice, you just use the log payment button to deduct the prepayment