Rate Limiting

The cNGN API rate-limits requests per API key, so each merchant has an independent budget regardless of source IP.

Limit	Value
Requests	20 per 60 seconds per API key
Block duration when exceeded	60 seconds

When you exceed the limit

The API responds with HTTP 429:

{
  "status": 429,
  "message": "Too many requests. Please try again later."
}

Once blocked, all requests with that key are rejected for 60 seconds.

Back off on 429: wait at least 60 seconds before retrying; retrying earlier extends nothing and wastes quota.
Cache stable data: bank lists (Get Banks) and supported networks (Get Networks) change rarely; cache them for hours, not seconds.
Batch reads: use pagination with a higher limit on Get Transactions instead of many small pages.
Poll responsibly: for withdrawal status, poll Verify Withdrawal with exponential backoff rather than a tight loop.