Hi Győző, the not_found error should indicate that "The file where the URL is saved to no longer exists". Is there any other activity in the account that might be causing this?
If not, meaning you're getting the not_found error when the file is successfully getting saved, and isn't being deleted or moved by something else, that sounds like a bug. In that case, please share some sample requests and responses (including response headers ideally, but please redact the access token) so that we can look into it. Thanks in advance!
Thanks! Can you share an actual URL and path (for the parameters to the intial call to /2/files/save_url) that reproduces this though? I can't reproduce this yet, so I suspect the specific values you're using may be relevant.
You can open a ticket here if you'd prefer to share privately:
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