我是在tp5 的根目录下执行 composer require topthink/think-captcha的 一直提示 下面的错误，请教下大神这个是个什么错！

[Composer\Downloader\TransportException]
Content-Length mismatch


require [--dev] [--prefer-source] [--prefer-dist] [--no-progress] [--no-suggest]
[--no-update] [--no-scripts] [--update-no-dev] [--update-with-dependencies] [--
ignore-platform-reqs] [--prefer-stable] [--prefer-lowest] [--sort-packages] [-o|
--optimize-autoloader] [-a|--classmap-authoritative] [--apcu-autoloader] [--] [<
packages>]...