diff --git a/invoices/invoiceregistry.go b/invoices/invoiceregistry.go
index a5570a3c..2cbba30e 100644
--- a/invoices/invoiceregistry.go
+++ b/invoices/invoiceregistry.go
@@ -437,10 +437,10 @@ func (i *InvoiceRegistry) checkHtlcParameters(invoice *channeldb.Invoice,
 		return channeldb.ErrInvoiceAlreadyCanceled
 	}
 
-	// If a payment has already been made, we only accept more payments if
-	// the amount is the exact same. This prevents probing with small
-	// amounts on settled invoices to find out the receiver node.
-	if invoice.AmtPaid != 0 && amtPaid != invoice.AmtPaid {
+	// If an invoice amount is specified, check that enough is paid. Also
+	// check this for duplicate payments if the invoice is already settled
+	// or accepted.
+	if invoice.Terms.Value > 0 && amtPaid < invoice.Terms.Value {
 		return ErrInvoiceAmountTooLow
 	}
 
@@ -468,11 +468,6 @@ func (i *InvoiceRegistry) checkHtlcParameters(invoice *channeldb.Invoice,
 		return ErrInvoiceExpiryTooSoon
 	}
 
-	// If an invoice amount is specified, check that enough is paid.
-	if invoice.Terms.Value > 0 && amtPaid < invoice.Terms.Value {
-		return ErrInvoiceAmountTooLow
-	}
-
 	return nil
 }
 
diff --git a/invoices/invoiceregistry_test.go b/invoices/invoiceregistry_test.go
index 990bcdc4..d8b8a5fe 100644
--- a/invoices/invoiceregistry_test.go
+++ b/invoices/invoiceregistry_test.go
@@ -165,9 +165,9 @@ func TestSettleInvoice(t *testing.T) {
 		t.Fatal("expected settle event")
 	}
 
-	// Try to settle again with a higher amount. This should result in a
-	// cancel event because after a restart the amount should still be the
-	// same. New HTLCs with a different amount should be rejected.
+	// Try to settle again with a higher amount. This payment should also be
+	// accepted, to prevent any change in behaviour for a paid invoice that
+	// may open up a probe vector.
 	event, err = registry.NotifyExitHopHtlc(
 		hash, amtPaid+600, testHtlcExpiry, testCurrentHeight,
 		hodlChan, nil,
@@ -175,12 +175,12 @@ func TestSettleInvoice(t *testing.T) {
 	if err != nil {
 		t.Fatalf("unexpected NotifyExitHopHtlc error: %v", err)
 	}
-	if event.Preimage != nil {
-		t.Fatal("expected cancel event")
+	if event.Preimage == nil {
+		t.Fatal("expected settle event")
 	}
 
-	// Try to settle again with a lower amount. This should show the same
-	// behaviour as settling with a higher amount.
+	// Try to settle again with a lower amount. This should fail just as it
+	// would have failed if it were the first payment.
 	event, err = registry.NotifyExitHopHtlc(
 		hash, amtPaid-600, testHtlcExpiry, testCurrentHeight,
 		hodlChan, nil,