Hi LiamSFS,
I appreciate your reaching out. When entering supplier payment, you will receive this warning message when the amount you have entered isn't equivalent to or more than the exact payment amount. A debit note will be created and will go to the Returns and Debits tab.
On the contrary, entering the exact amount of the supplier payment will get rid of the warning message.
Feel free to start a new post again if you require any assistance.
If my response has answered your inquiry, please click "Accept as Solution" to help other users find this.
Kind regards,
Shella