Inject nestjs service from another module

You have to export the ItemsService in the module that provides it:

@Module({  controllers: [ItemsController],  providers: [ItemsService],  exports: [ItemsService]  ^^^^^^^^^^^^^^^^^^^^^^^})export class ItemsModule {}

and then import the exporting module in the module that uses the service:

@Module({  controllers: [PlayersController],  providers: [PlayersService],  imports: [ItemsModule]  ^^^^^^^^^^^^^^^^^^^^^^})export class PlayersModule {}

⚠️ Do not add the same provider to multiple modules. Export the provider, import the module. ⚠️

Let' say you want to use AuthService from AuthModule in my TaskModule's controller

for that, you need to export authService from AuthModule

@Module({    imports: [     ....    ],    providers: [AuthService],    controllers: [AuthController],    exports:[AuthService]  })export class AuthModule {}  

then in TaskModule, you need to import AuthModule (note: import AuthModule not the AuthService in TaskModule)

@Module({    imports:[      AuthModule    ],    controllers: [TasksController],    providers: [TasksService]  })export class TasksModule {}

Now you should be able to use DI in TaskController

@Controller('tasks')export class TasksController {   constructor(private authService: AuthService) {}   ...}  

I solved my problem by removing @Inject() from the argument in my constructor that was passing the exported service.