diff --git a/service/waffo_pancake.go b/service/waffo_pancake.go
index 766a686d..5387eab8 100644
--- a/service/waffo_pancake.go
+++ b/service/waffo_pancake.go
@@ -103,6 +103,9 @@ func CreateWaffoPancakeCheckoutSession(ctx context.Context, params *WaffoPancake
 	if strings.TrimSpace(params.BuyerIdentity) == "" {
 		return nil, fmt.Errorf("missing buyer identity")
 	}
+	if strings.TrimSpace(params.OrderMerchantExternalID) == "" {
+		return nil, fmt.Errorf("missing order merchant external id")
+	}
 	client, err := newWaffoPancakeClient()
 	if err != nil {
 		return nil, fmt.Errorf("build Waffo Pancake client: %w", err)
diff --git a/service/waffo_pancake_test.go b/service/waffo_pancake_test.go
index 6f89f045..41c91a15 100644
--- a/service/waffo_pancake_test.go
+++ b/service/waffo_pancake_test.go
@@ -1,6 +1,7 @@
 package service
 
 import (
+	"context"
 	"fmt"
 	"strings"
 	"testing"
@@ -40,18 +41,29 @@ func setupWaffoPancakeTestDB(t *testing.T) *gorm.DB {
 	return db
 }
 
+func TestCreateWaffoPancakeCheckoutSession_RequiresOrderMerchantExternalID(t *testing.T) {
+	session, err := CreateWaffoPancakeCheckoutSession(context.Background(), &WaffoPancakeCreateSessionParams{
+		ProductID:     "PROD_checkout_guard",
+		BuyerIdentity: WaffoPancakeBuyerIdentityFromUserID(1),
+	})
+
+	require.Error(t, err)
+	require.Nil(t, session)
+	require.Contains(t, err.Error(), "missing order merchant external id")
+}
+
 func TestResolveWaffoPancakeTradeNo_UsesWebhookOrderIDWhenLocalOrderExists(t *testing.T) {
 	db := setupWaffoPancakeTestDB(t)
 
 	topUp := &model.TopUp{
-		UserId:        1,
-		Amount:        10,
-		Money:         29,
-		TradeNo:       "ORD_5dXBtmF2HLlHfbPNm0Wcnz",
+		UserId:          1,
+		Amount:          10,
+		Money:           29,
+		TradeNo:         "ORD_5dXBtmF2HLlHfbPNm0Wcnz",
 		PaymentMethod:   model.PaymentMethodWaffoPancake,
 		PaymentProvider: model.PaymentProviderWaffoPancake,
-		CreateTime:    time.Now().Unix(),
-		Status:        common.TopUpStatusPending,
+		CreateTime:      time.Now().Unix(),
+		Status:          common.TopUpStatusPending,
 	}
 	require.NoError(t, db.Create(topUp).Error)
 
@@ -70,14 +82,14 @@ func TestResolveWaffoPancakeTradeNo_RejectsBuyerIdentityMismatch(t *testing.T) {
 	db := setupWaffoPancakeTestDB(t)
 
 	topUp := &model.TopUp{
-		UserId:        42,
-		Amount:        10,
-		Money:         29,
-		TradeNo:       "ORD_identity_mismatch_case",
+		UserId:          42,
+		Amount:          10,
+		Money:           29,
+		TradeNo:         "ORD_identity_mismatch_case",
 		PaymentMethod:   model.PaymentMethodWaffoPancake,
 		PaymentProvider: model.PaymentProviderWaffoPancake,
-		CreateTime:    time.Now().Unix(),
-		Status:        common.TopUpStatusPending,
+		CreateTime:      time.Now().Unix(),
+		Status:          common.TopUpStatusPending,
 	}
 	require.NoError(t, db.Create(topUp).Error)
 
@@ -99,14 +111,14 @@ func TestResolveWaffoPancakeTradeNo_RejectsMissingBuyerIdentity(t *testing.T) {
 	db := setupWaffoPancakeTestDB(t)
 
 	topUp := &model.TopUp{
-		UserId:        7,
-		Amount:        10,
-		Money:         29,
-		TradeNo:       "ORD_missing_identity",
+		UserId:          7,
+		Amount:          10,
+		Money:           29,
+		TradeNo:         "ORD_missing_identity",
 		PaymentMethod:   model.PaymentMethodWaffoPancake,
 		PaymentProvider: model.PaymentProviderWaffoPancake,
-		CreateTime:    time.Now().Unix(),
-		Status:        common.TopUpStatusPending,
+		CreateTime:      time.Now().Unix(),
+		Status:          common.TopUpStatusPending,
 	}
 	require.NoError(t, db.Create(topUp).Error)
 
@@ -136,14 +148,14 @@ func TestResolveWaffoPancakeTradeNo_FailsWhenWebhookOrderIDIsUnknown(t *testing.
 	require.NoError(t, db.Create(user).Error)
 
 	topUp := &model.TopUp{
-		UserId:        user.Id,
-		Amount:        10,
-		Money:         29,
-		TradeNo:       "WAFFO_PANCAKE-42-123456-abc123",
+		UserId:          user.Id,
+		Amount:          10,
+		Money:           29,
+		TradeNo:         "WAFFO_PANCAKE-42-123456-abc123",
 		PaymentMethod:   model.PaymentMethodWaffoPancake,
 		PaymentProvider: model.PaymentProviderWaffoPancake,
-		CreateTime:    time.Now().Unix(),
-		Status:        common.TopUpStatusPending,
+		CreateTime:      time.Now().Unix(),
+		Status:          common.TopUpStatusPending,
 	}
 	require.NoError(t, db.Create(topUp).Error)
 
diff --git a/web/classic/src/components/settings/PaymentSetting.jsx b/web/classic/src/components/settings/PaymentSetting.jsx
index d2d35558..88000112 100644
--- a/web/classic/src/components/settings/PaymentSetting.jsx
+++ b/web/classic/src/components/settings/PaymentSetting.jsx
@@ -52,9 +52,6 @@ const PaymentSetting = () => {
     StripeMinTopUp: 1,
     StripePromotionCodesEnabled: false,
 
-    WaffoPancakeMerchantID: '',
-    WaffoPancakePrivateKey: '',
-    WaffoPancakeReturnURL: '',
     'payment_setting.compliance_confirmed': false,
     'payment_setting.compliance_terms_version': '',
     'payment_setting.compliance_confirmed_at': 0,
@@ -165,11 +162,6 @@ const PaymentSetting = () => {
           case 'StripeMinTopUp':
             newInputs[item.key] = parseFloat(item.value);
             break;
-          case 'WaffoPancakeMerchantID':
-          case 'WaffoPancakePrivateKey':
-          case 'WaffoPancakeReturnURL':
-            newInputs[item.key] = item.value;
-            break;
           default:
             if (item.key.endsWith('Enabled')) {
               newInputs[item.key] = toBoolean(item.value);
@@ -304,13 +296,6 @@ const PaymentSetting = () => {
                   hideSectionTitle
                 />
               </Tabs.TabPane>
-              <Tabs.TabPane tab={t('Waffo Pancake 设置')} itemKey='waffo-pancake'>
-                <SettingsPaymentGatewayWaffoPancake
-                  options={inputs}
-                  refresh={onRefresh}
-                  hideSectionTitle
-                />
-              </Tabs.TabPane>
               <Tabs.TabPane tab={t('Waffo 设置')} itemKey='waffo'>
                 <SettingsPaymentGatewayWaffo
                   options={inputs}