Why does the VK API audio.get give an incomplete response?

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Let's say there is a contact user who has 85 songs. I am writing a method that requests 100 songs per request. I'm debugging the method, I see that the request is not getting 100 songs, but less. As a result, instead of 1 request, the program makes 3-4 requests. And then he generally clogs up on the last song, which for some reason does not give contact. Why is that?