settings_changed
Status 409. The programme changed after it was read, so nothing was changed.
What it means
The programme was changed after the reading this change was built over: the one named by your if_version, or the one the API made itself to build the change, so that a change made in your Shopify admin or by another key in between is never quietly undone. Nothing was changed.
What to do
Read the programme again with GET /stores/{store_key}/programme, check the change still makes sense against it, and send it with a new Idempotency-Key.
Safe to send again?
Not as it is. Change what the answer points to, then send the request.
Where you can meet it
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 expirePOST /stores/{store_key}/programme/rewards: Add a reward shoppers can spend points onPOST /stores/{store_key}/programme/rewards/{reward_id}: Change a reward's cost, value, minimum order or labelPOST /stores/{store_key}/programme/rewards/{reward_id}/remove: Remove a rewardPOST /stores/{store_key}/programme/offers: Add an offer: a campaign, a product offer or a channel offerPOST /stores/{store_key}/programme/offers/{offer_id}: Change an offerPOST /stores/{store_key}/programme/offers/{offer_id}/remove: Remove an offerPOST /stores/{store_key}/design: Change the design: colours, words, the panel and product-line look, the account page layout, the terms link
Every code, and the shape of an error answer: Errors.