curl "https://secureapi.gridlog.io/api/v1/pos/sessions/countries" \
  -H "X-API-Key: YOUR_API_KEY"

{
  "countries": [
    {
      "code": "NG",
      "name": "Nigeria",
      "currency": "NGN"
    },
    {
      "code": "KE",
      "name": "Kenya",
      "currency": "KES"
    },
    {
      "code": "GH",
      "name": "Ghana",
      "currency": "GHS"
    }
  ]
}