curl --location 'https://verify.veloconnect.me/v1/billing/topup' \
--header 'Content-Type: application/json' \
--data '{
"amount_usd": 100,
"success_url": "https://example.com/billing/success",
"cancel_url": "https://example.com/billing/cancel"
}'{
"checkout_url": "string"
}