diff --git a/Elwig/Helpers/Billing/BillingData.cs b/Elwig/Helpers/Billing/BillingData.cs
index 80c83d5..94bc815 100644
--- a/Elwig/Helpers/Billing/BillingData.cs
+++ b/Elwig/Helpers/Billing/BillingData.cs
@@ -146,7 +146,12 @@ namespace Elwig.Helpers.Billing {
             return dict;
         }
 
-        protected static Dictionary<string, JsonValue> GetSelection(JsonObject data, IEnumerable<string> attributeVariants) {
+        protected static Dictionary<string, JsonValue> GetSelection(JsonNode value, IEnumerable<string> attributeVariants) {
+            if (value is JsonValue flatRate) {
+                return attributeVariants.ToDictionary(e => e, _ => flatRate);
+            } if (value is not JsonObject data) {
+                throw new InvalidOperationException();
+            }
             Dictionary<string, JsonValue> dict;
             if (data["default"] is JsonValue def) {
                 dict = attributeVariants.ToDictionary(e => e, _ => def);
diff --git a/Elwig/Helpers/Billing/PaymentBillingData.cs b/Elwig/Helpers/Billing/PaymentBillingData.cs
index ec80cbd..0c1535d 100644
--- a/Elwig/Helpers/Billing/PaymentBillingData.cs
+++ b/Elwig/Helpers/Billing/PaymentBillingData.cs
@@ -25,17 +25,12 @@ namespace Elwig.Helpers.Billing {
             return new(ParseJson(json), attributeVariants);
         }
 
-        private Dictionary<string, Curve> GetData(JsonObject data) {
+        private Dictionary<string, Curve> GetData(JsonNode data) {
             return GetSelection(data, AttributeVariants).ToDictionary(e => e.Key, e => LookupCurve(e.Value));
         }
 
         protected Dictionary<string, Curve> GetPaymentData() {
-            var p = GetPaymentEntry();
-            if (p is JsonValue val) {
-                var c = LookupCurve(val);
-                return AttributeVariants.ToDictionary(e => e, _ => c);
-            }
-            return GetData(p?.AsObject() ?? throw new InvalidOperationException());
+            return GetData(GetPaymentEntry());
         }
 
         protected Dictionary<string, Curve> GetQualityData() {
@@ -44,14 +39,7 @@ namespace Elwig.Helpers.Billing {
             if (q == null) return dict;
 
             foreach (var (qualid, data) in q) {
-                Dictionary<string, Curve> qualDict;
-                if (data is JsonValue val) {
-                    var c = LookupCurve(val);
-                    qualDict = AttributeVariants.ToDictionary(e => e, _ => c);
-                } else {
-                    qualDict = GetData(data?.AsObject() ?? throw new InvalidOperationException());
-                }
-                foreach (var (idx, d) in qualDict) {
+                foreach (var (idx, d) in GetData(data ?? throw new InvalidOperationException())) {
                     dict[$"{qualid}/{idx}"] = d;
                 }
             }