GrantItemsToUser currently does not allow to set the quantity to be granted and asumes is always one. Multiple requests have to be created and send in order to grant items in amounts higher than one.
I think this is a very much needed feature for a better and cleaner code.
Including the item's ID multiple times in the "ItemIds" array works pretty well, but it is not a great solution and it does not leave a very clean code in my opinion.
Thanks for posting it as a feature request!
Thanks to @Víctor suggestion, I tried adding multiple times the same item id, and it works correctly, even with stackable items (remaining uses are properly incremented by the number of times the item id is introduced in the list).
So while this is not a very elegant approach, it does indeed work perfectly for the purpose, and thus the request is no longer regarding a missing feature. I tend to think the request can be disregarded.
The request is still valid, please don't remove it. It's super ugly to include the item multiple times. Also, it's probably related to the PlayFab internal limits which prevent you from granting LOTS of items in one call. They say you shouldn't give more than 50 or the request can time out.
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