diff --git a/server/src/main/java/haengdong/user/domain/User.java b/server/src/main/java/haengdong/user/domain/User.java
index 19c886d73..438482d2c 100644
--- a/server/src/main/java/haengdong/user/domain/User.java
+++ b/server/src/main/java/haengdong/user/domain/User.java
@@ -36,7 +36,7 @@ public class User extends BaseEntity {
     @Column(length = MAX_ACCOUNT_NUMBER_LENGTH)
     private String accountNumber;
 
-    @Column(unique = true, nullable = false)
+    @Column(unique = true)
     private String memberNumber;
 
     private User(String nickname, String password, String bank, String accountNumber, String memberNumber) {
diff --git a/server/src/test/java/haengdong/application/EventServiceTest.java b/server/src/test/java/haengdong/application/EventServiceTest.java
index 288cb775d..eb82a6b90 100644
--- a/server/src/test/java/haengdong/application/EventServiceTest.java
+++ b/server/src/test/java/haengdong/application/EventServiceTest.java
@@ -7,12 +7,7 @@
 import static org.junit.jupiter.api.Assertions.assertAll;
 import static org.mockito.BDDMockito.given;
 
-import java.util.List;
-import org.junit.jupiter.api.DisplayName;
-import org.junit.jupiter.api.Test;
-import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.beans.factory.annotation.Value;
-import org.springframework.boot.test.mock.mockito.MockBean;
+import haengdong.common.exception.HaengdongException;
 import haengdong.event.application.EventService;
 import haengdong.event.application.request.EventGuestAppRequest;
 import haengdong.event.application.request.EventUpdateAppRequest;
@@ -24,13 +19,17 @@
 import haengdong.event.domain.bill.Bill;
 import haengdong.event.domain.bill.BillRepository;
 import haengdong.event.domain.event.Event;
+import haengdong.event.domain.event.EventRepository;
 import haengdong.event.domain.event.image.EventImage;
 import haengdong.event.domain.event.image.EventImageRepository;
-import haengdong.event.domain.event.EventRepository;
 import haengdong.event.domain.event.member.EventMember;
 import haengdong.event.domain.event.member.EventMemberRepository;
-import haengdong.common.exception.HaengdongException;
 import haengdong.support.fixture.Fixture;
+import java.util.List;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.mock.mockito.MockBean;
 
 class EventServiceTest extends ServiceTestSupport {