TypeORM. Cannot perform update query because update values are not defined. Call \"qb.set(...)\" method to specify updated values

Question

I am new to TypeORM. I'm using MySQL DB and ExpressJS app.

I have 2 entities: User and Client. There's one-to-one relationship between them. Client has foreign key. I get following error when I save a client:

Cannot perform update query because update values are not defined. Call "qb.set(...)" method to specify updated values

User Entity:

export class User extends BaseEntity {
  @PrimaryGeneratedColumn()
  id: number

  @Column()
  role: string

  @Column()
  email: string

  @Column()
  password: string

  @Column({ default: '' })
  avatar: string

  @Column()
  firstName: string

  @Column()
  lastName: string

  @Column()
  fullName: string

  @Column({ default: '' })
  phone: string

  @Column({ type: 'text', nullable: true })
  description: string

  @Column({ nullable: true })
  age: number

  @OneToOne(_type => Freelancer, freelancer => freelancer.user, { nullable: true })
  freelancer: Freelancer

  @OneToOne(_type => Client, client => client.user, { nullable: true })
  client: Client
}

Client Entity:

@Entity()
export class Client extends BaseEntity {
  @PrimaryGeneratedColumn()
  id: number

  @Column()
  companyName: string

  @ManyToOne(_type => Position, position => position.clients)
  position: Position

  @OneToOne(_type => ClientReview, clientReview => clientReview.client, { nullable: true })
  @JoinColumn()
  review: ClientReview

  @OneToMany(_type => Project, project => project.client, { nullable: true })
  projects: Project[]

  @OneToOne(_type => User, user => user.client)
  @JoinColumn()
  user: User
}

Code in auth.service, where I save client. Just overview:

const user = userRepository.create({
      email,
      password: hashedPassword,
      role,
      description,
      firstName,
      lastName,
      fullName: `${firstName} ${lastName}`,
      phone
    })


      const clientRepository = getRepository(Client)
      const positionRepository = getRepository(Position)

      const positionEntity = await positionRepository.findOne({ id: position.id })


      const client = clientRepository.create({
        companyName,
        position: positionEntity,
        user
      })

      await userRepository.save(user)
      await clientRepository.save(client)

The problem is in user column of Client entity, as when I remove it, everything works, but Client and User are saved separately and do not have any relation between each other, obviously.

So, my questions are What I did wrong and How should I fix it? Thanks for the answer beforehand