`idempotency_key_in_use`

Status 409. A request with this Idempotency-Key is still being processed.

What it means

The first request with this Idempotency-Key is still being processed.

Wait the number of seconds in Retry-After, then send the same request again to get its answer. Do not change the key: a new key is a new change.

Yes, after waiting the number of seconds in Retry-After.

POST /stores/{store_key}/programme: Change the earn rate, the bonuses, what a point is worth, referrals, spending any amount, the time zone, the ways to earn, or when points expire
POST /stores/{store_key}/programme/rewards: Add a reward shoppers can spend points on
POST /stores/{store_key}/programme/rewards/{reward_id}: Change a reward's cost, value, minimum order or label
POST /stores/{store_key}/programme/rewards/{reward_id}/remove: Remove a reward
POST /stores/{store_key}/programme/offers: Add an offer: a campaign, a product offer or a channel offer
POST /stores/{store_key}/programme/offers/{offer_id}: Change an offer
POST /stores/{store_key}/programme/offers/{offer_id}/remove: Remove an offer
POST /stores/{store_key}/design: Change the design: colours, words, the panel and product-line look, the account page layout, the terms link
POST /members/{member_key}/adjustments: Add points to a member's balance, or take them away
POST /members/{member_key}/codes/void: Cancel a reward code and give the member back its points

Every code, and the shape of an error answer: Errors.