curl --request POST \
  --url https://sandbox-biller-b2b.singapay.id/api/v2/postpaid/inquiry \
  --header 'Accept: <accept>' \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: <content-type>' \
  --header 'X-PARTNER-ID: <x-partner-id>' \
  --data '
{
  "command": "plnpos",
  "data": {
    "customer_id": "114676170021",
    "product_code": "SPPLNPOS"
  }
}
'

{
  "command": "plnpos",
  "response_code": "00",
  "response_text": "Inquiry success",
  "data": {
    "amount": "69674",
    "customer_name": "JOHN DOE",
    "period": "4",
    "late_fee": "36000",
    "customer_id": "114676170021",
    "reference_number": "SPPLNPOSRJBL0057437746821761805651",
    "price": "74194",
    "created_at": "2025-10-30 13:27:31"
  }
}