curl --request POST \
  --url https://api.grailpay.com/3p/api/v1/bank-account/balance/{user_uuid} \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "amount": 2,
  "billing_merchant_user_uuid": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
  "billing_processor_mid": "<string>"
}
'

{
  "status": true,
  "message": "",
  "data": {
    "available_balance": 1000
  },
  "errors": null,
  "error_code": null
}