diff --git a/backend/src/album/album.entity.ts b/backend/src/album/album.entity.ts
index 6e2be92..dc613e0 100644
--- a/backend/src/album/album.entity.ts
+++ b/backend/src/album/album.entity.ts
@@ -1,5 +1,5 @@
 import { Entity, Column, OneToMany, PrimaryGeneratedColumn } from 'typeorm';
-import { Song } from '@/song/song.entity';
+import { Song } from '../song/song.entity';
 
 @Entity()
 export class Album {
diff --git a/backend/src/album/album.service.spec.ts b/backend/src/album/album.service.spec.ts
index d6fdab3..266abb4 100644
--- a/backend/src/album/album.service.spec.ts
+++ b/backend/src/album/album.service.spec.ts
@@ -1,12 +1,28 @@
 import { Test, TestingModule } from '@nestjs/testing';
+import { getRepositoryToken } from '@nestjs/typeorm';
 import { AlbumService } from './album.service';
+import { Album } from './album.entity';
+
+const mockAlbum = new Album();
 
 describe('AlbumService', () => {
   let service: AlbumService;
 
   beforeEach(async () => {
     const module: TestingModule = await Test.createTestingModule({
-      providers: [AlbumService],
+      providers: [
+        AlbumService,
+        {
+          provide: getRepositoryToken(Album),
+          useValue: {
+            findAll: jest.fn().mockResolvedValue([mockAlbum]),
+            findOneById: jest.fn().mockResolvedValue(mockAlbum),
+            create: jest.fn().mockResolvedValue(1),
+            update: jest.fn().mockResolvedValue("Album updated successfully"),
+            remove: jest.fn().mockResolvedValue(null),
+          },
+        },
+      ]
     }).compile();
 
     service = module.get<AlbumService>(AlbumService);
diff --git a/backend/src/song/song.entity.ts b/backend/src/song/song.entity.ts
index 9325cb7..086cc88 100644
--- a/backend/src/song/song.entity.ts
+++ b/backend/src/song/song.entity.ts
@@ -1,5 +1,5 @@
 import { Entity, Column, ManyToOne, PrimaryGeneratedColumn } from 'typeorm';
-import { Album } from '@/album/album.entity';
+import { Album } from '../album/album.entity';
 
 @Entity()
 export class Song {
diff --git a/backend/src/song/song.service.spec.ts b/backend/src/song/song.service.spec.ts
index c7b9a7d..b02a751 100644
--- a/backend/src/song/song.service.spec.ts
+++ b/backend/src/song/song.service.spec.ts
@@ -1,12 +1,28 @@
 import { Test, TestingModule } from '@nestjs/testing';
+import { getRepositoryToken } from '@nestjs/typeorm';
 import { SongService } from './song.service';
+import { Song } from './song.entity';
+
+const mockSong = new Song();
 
 describe('SongService', () => {
   let service: SongService;
 
   beforeEach(async () => {
     const module: TestingModule = await Test.createTestingModule({
-      providers: [SongService],
+      providers: [
+        SongService,
+        {
+          provide: getRepositoryToken(Song),
+          useValue: {
+            findAll: jest.fn().mockResolvedValue([mockSong]),
+            findOneById: jest.fn().mockResolvedValue(mockSong),
+            create: jest.fn().mockResolvedValue(1),
+            update: jest.fn().mockResolvedValue("Song updated successfully"),
+            remove: jest.fn().mockResolvedValue(null),
+          },
+        },
+      ]
     }).compile();
 
     service = module.get<SongService>(SongService);
diff --git a/backend/src/song/song.service.ts b/backend/src/song/song.service.ts
index 58809c1..9afdaad 100644
--- a/backend/src/song/song.service.ts
+++ b/backend/src/song/song.service.ts
@@ -29,7 +29,7 @@ export class SongService {
     return savedSong.id;
   }
 
-  async update(updateSongDto: UpdateSongDto): Promise<string> {
+  async update(id: number, updateSongDto: UpdateSongDto): Promise<string> {
     if (id === updateSongDto.id) {
       const song = this.songRepository.findOneBy({ id: updateSongDto.id });
       if (!song)