PHP $ _FILES ['name'] ['type']返回空值

So I'm trying to upload multiple mp3 files at once and only one was being uploaded. I did some tracing and it turns out that for some reason, some of the file types are returning empty values, so I think as a result they are not being uploaded. I'm not too sure though and my research hasn't yielded much because I don't know exactly what to research at this point.

Here's the array that's being returned when I upload multiple mp3 files.

Array
(
    [name] => Array
        (
            [0] => a.mp3
            [1] => e.mp3
            [2] => s.mp3
        )

    [type] => Array
        (
            [0] => 
            [1] => audio/mp3
            [2] => 
        )

    [tmp_name] => Array
        (
            [0] => 
            [1] => /private/var/tmp/phpfqxWTx
            [2] => 
        )

    [error] => Array
        (
            [0] => 1
            [1] => 0
            [2] => 1
        )

    [size] => Array
        (
            [0] => 0
            [1] => 1908445
            [2] => 0
        )

)

You just didn't check the most relevant field, error:

UPLOAD_ERR_INI_SIZE

Value: 1; The uploaded file exceeds the upload_max_filesize directive in php.ini.

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