checkoutCustomerAssociateV2.graphql

mutation checkoutCustomerAssociateV2($checkoutId: ID!, $customerAccessToken: String!) {
  checkoutCustomerAssociateV2(
    checkoutId: $checkoutId
    customerAccessToken: $customerAccessToken
  ) {
    checkout {
      id
    }
    checkoutUserErrors {
      code
      field
      message
    }
    customer {
      id
    }
  }
}