First reminder for unpaid outstanding invoice after the provision of goods and services that have been overdue. Suggest that there may have been an oversight.
We are writing in relation to Invoice Number for [Goods / Services]. The above sum was due for payment but as at today's date, we have yet to receive the payment of the outstanding amount of <[AMOUNT], which is now overdue.
We believe this may have been an oversight (please ignore this message if you have recently paid), we are resending you our bank account details for you to make the transfer as soon as possible: