diff --git a/internal/logic/public/order/getDiscount.go b/internal/logic/public/order/getDiscount.go
index ee7dd4e..db107f3 100644
--- a/internal/logic/public/order/getDiscount.go
+++ b/internal/logic/public/order/getDiscount.go
@@ -16,13 +16,23 @@ func getDiscount(discounts []types.SubscribeDiscount, inputMonths int64, isNewUs
 }
 
 // isNewUserOnlyForQuantity checks whether the matched discount tier has new_user_only enabled.
+// Returns true only when all matching tiers for the given quantity require new-user status
+// (i.e. no fallback tier with new_user_only=false exists). When both a new-user-only tier
+// and a general tier exist for the same quantity, non-new-users can still purchase via the
+// general tier, so this returns false.
 func isNewUserOnlyForQuantity(discounts []types.SubscribeDiscount, inputQuantity int64) bool {
-	for _, discount := range discounts {
-		if inputQuantity == discount.Quantity {
-			return discount.NewUserOnly
+	hasNewUserOnly := false
+	hasFallback := false
+	for _, d := range discounts {
+		if d.Quantity != inputQuantity {
+			continue
+		}
+		if d.NewUserOnly {
+			hasNewUserOnly = true
+		} else {
+			hasFallback = true
 		}
 	}
-
-	return false
+	return hasNewUserOnly && !hasFallback
 }
 
diff --git a/queue/logic/order/activateOrderLogic.go b/queue/logic/order/activateOrderLogic.go
index 45a41cc..582f595 100644
--- a/queue/logic/order/activateOrderLogic.go
+++ b/queue/logic/order/activateOrderLogic.go
@@ -1319,12 +1319,22 @@ func (l *ActivateOrderLogic) RedemptionActivate(ctx context.Context, orderInfo *
 }
 
 // isNewUserOnlyForQuantity checks whether the matched discount tier has new_user_only enabled.
+// Returns true only when all matching tiers for the given quantity require new-user status
+// (i.e. no fallback tier with new_user_only=false exists). When both a new-user-only tier
+// and a general tier exist for the same quantity, non-new-users can still purchase via the
+// general tier, so this returns false.
 func isNewUserOnlyForQuantity(discounts []internaltypes.SubscribeDiscount, inputQuantity int64) bool {
+	hasNewUserOnly := false
+	hasFallback := false
 	for _, d := range discounts {
-		if inputQuantity == d.Quantity {
-			return d.NewUserOnly
+		if d.Quantity != inputQuantity {
+			continue
+		}
+		if d.NewUserOnly {
+			hasNewUserOnly = true
+		} else {
+			hasFallback = true
 		}
 	}
-
-	return false
+	return hasNewUserOnly && !hasFallback
 }