The NIP96 upload file is here:
https://github.com/haorendashu/nostr_sdk/blob/master/lib/upload/nip96_uploader.dart

I upload a test file and try to delete it.
1. Upload success.
2. Download success.
3. It seems first time i try to delete at https://nostr.build/delete/ it tell me *delete success* . 
4. But this file still can download.
5. And i try to delete this file again, it try me delete fail.

upload info:
file name: b89ad7e9d01d7002051847ac3762bb5b2191d9ae32b5df363d04545755892aa0.png
npub name: npub13jyr30u0x6uxzdcta0p2eh5dza0jhkglpp7mk3z7maej0ycamxgqw0y824 

 I tried using nostrmo from Mac desktop and was not able to detect authentication for the upload. I wonder if something is missing? 

 Have you change the image service to NIP96? If you select nostr.build upload service, it will try to use the old upload api.

https://image.nostr.build/15588a8ca6d59e88913b3516929426ea0fbbdf4acd31c87e6fc3ffa7dd069e62.jpg 

 I just used default one, so I guess that’s where the problem lies 

 Did you know that you could also pass nip98 header to the old api and achieve the same result? 

 Maybe i should change the default nostr.build upload method to nip96? 

 That’ll work too 

 If the file is a duplicate of the previously uploaded one then it will only delete your npub association 

 Yes, this file i had uploaded many times 🤣 

 lol, that explains it then 😂 

 The easiest way to verify if you fully own the upload is by checking media’s http headers. See examples for your file and mine. https://i.nostr.build/FioOg82pmTIii3we.jpg https://i.nostr.build/hBGRoOWlGsZAIZ57.jpg