Temporary files tend to grow with times and can quickly become the reason your disk space has shrinked. Below you can find a snippet which will help you to clean the your app temporary folder from outdated files. There is a time frame set to define for how long to keep the files. This is curretly set to delete files older than 1 day, which you free change as best fits your app.

$fileList = \Storage::disk('media')->allFiles('temp');
$deletedFileCount = 0;
foreach ($fileList as $filePath) {
    $lastModified = \Storage::disk('media')->lastModified($filePath);
    $keepTime = time() - 1 * 24 * 60 * 60; // 1 day
    if ($lastModified < $keepTime) {
        \Storage::disk('media')->delete($filePath);
        $deletedFileCount++;
    }
}
$this->comment('  - Deleted ' . $deletedFileCount . ' files');

Add this as a job to the scheduler to run every day and off you go.