I would like to give several people a membership, linked to 1 payment

• person A: membership (+ contribution)
• person B: membership (related to membership person A)

$contact_a = 2;
$contact_b = 3;

$contribution = civicrm_api3('Contribution', 'create', [
  'financial_type_id' => 2,
  'contact_id' => (int) $contact_a,
  'contribution_status_id' => 2,
  'total_amount' => 50,
  'is_pay_later' => 1,
]);

$main_membership = civicrm_api3('Membership', 'create', [
  'contact_id' => (int) $contact_a,
  'membership_type_id' => 1,
  'status_id' => 5,
  'skipStatusCal' => 1,
]);

$part_membership = civicrm_api3('Membership', 'create', [
  'contact_id' => (int) $contact_b,
  'owner_membership_id' => $main_membership['id'],
  'membership_type_id' => 1,
  'status_id' => 5,
  'skipStatusCal' => 1,
]);

$memb_payment = civicrm_api3('MembershipPayment', 'create', [
  'membership_id' => (int) $main_membership['id'],
  'contribution_id' => (int) $contribution['id'],
]);

This seems correct, person A gets a membership & contribution, person B gets a membership related to the membership of person A.

As soon as I process the membership payment via the API the contribution is complete and the membership for person A becomes active, BUT the membership for person B is deleted !?

$complete = civicrm_api3('Contribution', 'completetransaction', [
	'id' => 9, 
	'is_email_receipt' => 0
]);

I have simplified the operation to only the membership registrations:

$contact_a = 2;
$contact_b = 3;

$main_membership = civicrm_api3('Membership', 'create', [
  'contact_id' => (int) $contact_a,
  'membership_type_id' => 1,
  'status_id' => 5,
  'skipStatusCal' => 1,
]);

$part_membership = civicrm_api3('Membership', 'create', [
  'contact_id' => (int) $contact_b,
  'owner_membership_id' => $main_membership['id'],
  'membership_type_id' => 1,
  'status_id' => 5,
  'skipStatusCal' => 1,
]);

And if I then set the membership of person A to "New" the membership of person B is deleted !?

$new = civicrm_api3('Membership', 'create', [
  'id' => 39,
  'status_id' => "New",
]);

The problem therefore lies somewhere with the update of the membership of person A.

Does anyone have an idea?