Inject nestjs service from another module?

Answer

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 {}