curl -X POST https://api.titan.global/v1/payments
-H "Authorization: Bearer YOUR_ACCESS_TOKEN"
-H "Content-Type: application/json"
-d '{
"amount": 2500.00,
"currency": "USD",
"customer_id": "cus_123456789",
"reference": "INV-2024-1001",
"callback_url": "https://yourapp.com/webhook",
}'