What's the difference between minimum dunning amount and minimum dunning invoice amount?

The minimum dunning amount is the total amount set for all overdue transactions to generate the correspondence.

If your minimum dunning amount is set to $100 and you have three overdue transactions of $25, $35, and $55. totaling to $105. A dunning letter is generated listing all the three invoices as overdue.

The minimum dunning invoice amount is the amount set for a single overdue transaction to generate correspondence. If your minimum dunning invoice amount is set to $25 and you have three overdue transactions of $15, $50, and $75. A dunning letter is generated only for the $50 and $75 transactions.