Valine comment appear twice

[shj37]

Though I use a modified version of Valine, the problem persists with the official version.

https://eduunited.org/2019/12/21/testcomment/

But has no such problem when comment is below credit section: https://eduunited.org/2019/12/21/postshare/

Please make sure these boxes are checked before submitting your issue. Thank you!

• [x] I have setuped and configurated the blog according to Hexo official documentation;
• [x] I have read the Theme Wiki carefully and created my own configuration file(_config.yml);
• [x] I have looked up the Issues and found no duplicate issues.

请在发布新Issue之前确保你已经进行了如下工作，谢谢！

• [x] 我已经按照Hexo官方文档中的步骤安装与配置了Hexo；
• [x] 我已经仔细地阅读了主题Wiki并创建了自己的配置文件(_config.yml)；
• [x] 我已经搜索了Issues，并且没有找到类似的问题。