I want to change the listing ID array using updateItemPriceMarkdownPromotion but not working

[productvaleur]

{
"name": "Save up to $13",
"description": "Save up to $13",
"startDate": "2023-03-12T13:50:24.000Z",
"endDate": "2023-04-23T12:52:25.000Z",
"marketplaceId": "EBAY_US",
"promotionStatus": "SCHEDULED",
"promotionImageUrl": imgurl,
"blockPriceIncreaseInItemRevision": true,
"autoSelectFutureInventory": "true",

"selectedInventoryDiscounts": [{
"inventoryCriterion": {
"inventoryCriterionType": "INVENTORY_BY_VALUE",

"listingIds": [
"1",
"2", 
"3",
]

},
"discountBenefit": {
"amountOffItem": {
"value": "13",
"currency": "USD"
}
},
"discountId": "discountId"
}]
}

this is my Call Request i try to remove number '2' from the array.

When I subtracted 2 and requested, the call response came out as 200.

However, as a result of actually checking through getItemPriceMarkdownPromotion, the number 2 was not cleared.

When I actually add an array, it works fine.
Deleting from an array does not work
What could be the problem?

[five_notch_trading_post]

I would suggest trying to see if the content returned from the call has any messages indicating errors.

The docs say you should get a 204 not a 200 on a proper success

Output

A successful call returns the HTTP status code 204 No Content, which indicates the promotion was updated as specified. This method has no response payload.

Also that json also has some issues, mixing true, and "true", the 2nd being a string and not boolean (whether the server decides to accept this I am not sure)

I assume the other discrepancies such as trailing commas are just from truncating the original (but in case not, double-check that your json is properly formed.)