The Checkissuing API supports idempotency so you can safely retry your requests without having to worry about a duplicate operation. All endpoints support passing an Idempotency-Key HTTP header as part of the request.
This should be a unique key no longer than 255 characters that will not be re-used with that particular endpoint or those parameters. If you make the same request with the same idempotent key, no action will be taken and the previous request's result will be returned. If you re-use an idempotent key with different parameters, the idempotent key will be ignored and the request will be processed as normal.
Idempotent keys only last for 48 hours. So if you repeat the same request and reuse the idempotent key after more than 48 hours, the request will be considered a new one and the idempotent key will be ignored.