diff --git a/web-admin/src/utils/collection-ledger-export.test.ts b/web-admin/src/utils/collection-ledger-export.test.ts
index d2a1738e..fba8db49 100644
--- a/web-admin/src/utils/collection-ledger-export.test.ts
+++ b/web-admin/src/utils/collection-ledger-export.test.ts
@@ -157,14 +157,15 @@ describe('buildResearchLedgerRows', () => {
 })
 
 describe('buildCustomerServiceLedgerRows', () => {
-  it('keeps identity numbers as text columns', () => {
+  it('fills protocol-number column with sample code', () => {
     const [row] = buildCustomerServiceLedgerRows([
       {
         labStorageCode: 'B0000002',
         protocolStatus: 'sxz',
         smsSendDate: '20250908',
         smsSendStatus: '已发',
-        protocolNo: 'ZKZX34000852',
+        sampleCode: 'ZKZX34000852',
+        protocolNo: 'PROTO-SHOULD-NOT-EXPORT',
         motherName: '高居巧',
         motherPhone: '17860507206',
         motherIdCard: '370911199712254424',
diff --git a/web-admin/src/utils/collection-ledger-export.ts b/web-admin/src/utils/collection-ledger-export.ts
index 3a145af9..ae5836f2 100644
--- a/web-admin/src/utils/collection-ledger-export.ts
+++ b/web-admin/src/utils/collection-ledger-export.ts
@@ -492,7 +492,7 @@ export function buildCustomerServiceLedgerRows(rows: Row[]): string[][] {
     String(index + 1),
     formatLedgerDate(row.smsSendDate),
     text(row.smsSendStatus),
-    text(row.protocolNo),
+    text(row.sampleCode),
     text(row.motherName),
     text(row.motherPhone),
     text(row.motherIdCard),