Create_new_entity_using_new_service.ts

// One more service, which do nothisn except create new instance with userId field
class oneSignalService {
  async create(user, data) {
    return this.repository.create<UserOneSignal>({
      userId: user.id,
      ...data,
    });
  }
}

@Component()
export class MeService {
  constructor(
    // must be injected one more service here,
    private readonly oneSignalService: OneSignalService,
  ) {}

  async someMethod(user, data) {
    // We should ignore the availability of the ready-made method within the library used, but use your exact same method
    await this.oneSignalService.create<UserOneSignal>(user, data);
  }

  async reusageInSecondPlace(user, data) {
    // We should ignore the availability of the ready-made method within the library used, but use your exact same method
    await this.oneSignalService.create<UserOneSignal>(user, data);
  }
}