diff --git a/server/skillhub-domain/src/main/java/com/iflytek/skillhub/domain/namespace/PersonalNamespaceProvisioningService.java b/server/skillhub-domain/src/main/java/com/iflytek/skillhub/domain/namespace/PersonalNamespaceProvisioningService.java
index b5b3bf81..8c42bac9 100644
--- a/server/skillhub-domain/src/main/java/com/iflytek/skillhub/domain/namespace/PersonalNamespaceProvisioningService.java
+++ b/server/skillhub-domain/src/main/java/com/iflytek/skillhub/domain/namespace/PersonalNamespaceProvisioningService.java
@@ -141,7 +141,7 @@ public class PersonalNamespaceProvisioningService {
         boolean truncated = false;
 
         for (int page = 0; !truncated; page++) {
-            Page<UserAccount> batch = userAccountRepository.search(null, UserStatus.ACTIVE,
+            Page<UserAccount> batch = userAccountRepository.findByStatus(UserStatus.ACTIVE,
                     PageRequest.of(page, BACKFILL_PAGE_SIZE, Sort.by("id")));
             if (batch.isEmpty()) {
                 break;
diff --git a/server/skillhub-domain/src/main/java/com/iflytek/skillhub/domain/user/UserAccountRepository.java b/server/skillhub-domain/src/main/java/com/iflytek/skillhub/domain/user/UserAccountRepository.java
index c0f4f295..bcfbb3b3 100644
--- a/server/skillhub-domain/src/main/java/com/iflytek/skillhub/domain/user/UserAccountRepository.java
+++ b/server/skillhub-domain/src/main/java/com/iflytek/skillhub/domain/user/UserAccountRepository.java
@@ -14,5 +14,16 @@ public interface UserAccountRepository {
     List<UserAccount> findByIdIn(List<String> ids);
     Optional<UserAccount> findByEmailIgnoreCase(String email);
     Page<UserAccount> search(String keyword, UserStatus status, Pageable pageable);
+
+    /**
+     * Lists accounts in one status.
+     *
+     * <p>Separate from {@link #search} on purpose: that query compares the keyword with
+     * {@code lower(...)}, and passing a null keyword leaves PostgreSQL to infer the bind type as
+     * {@code bytea}, which fails with "function lower(bytea) does not exist". Callers that want
+     * every account in a status have no keyword to give, so they get a query without one.
+     */
+    Page<UserAccount> findByStatus(UserStatus status, Pageable pageable);
+
     UserAccount save(UserAccount user);
 }
diff --git a/server/skillhub-domain/src/test/java/com/iflytek/skillhub/domain/namespace/PersonalNamespaceProvisioningServiceTest.java b/server/skillhub-domain/src/test/java/com/iflytek/skillhub/domain/namespace/PersonalNamespaceProvisioningServiceTest.java
index 559ff271..e3b8503a 100644
--- a/server/skillhub-domain/src/test/java/com/iflytek/skillhub/domain/namespace/PersonalNamespaceProvisioningServiceTest.java
+++ b/server/skillhub-domain/src/test/java/com/iflytek/skillhub/domain/namespace/PersonalNamespaceProvisioningServiceTest.java
@@ -63,7 +63,7 @@ class PersonalNamespaceProvisioningServiceTest {
     }
 
     private void directoryContains(UserAccount... users) {
-        when(userAccountRepository.search(isNull(), eq(UserStatus.ACTIVE), any()))
+        when(userAccountRepository.findByStatus(eq(UserStatus.ACTIVE), any()))
                 .thenReturn(new PageImpl<>(List.of(users)));
     }