The 2 episodes are here. They are S01E05 and S01E06.

请查看第五集是分上下的然后才是第五集Ⅱ

As you can see on the official site, these 2 parts form one single episode numbered 5. The episode "逃离废弃学校II" being numbered as episode 6.

这一集其实是三个部分，逃离废弃学校上 逃离废弃学校下 然后才是逃离废弃学校Ⅱ请您去芒果TV视频网站上看一下您就明白了！

The official (Mango TV) site consider the first 2 parts as being one single episode numbered 5. Consequently, we need to do the same here.

也就是说，这个错误是无法更改了是吗？

This can't be modified as we respect the numbering of the official site.

您尊重官方网站的编号，可是贵站的编号与官方并不一致，然后您还不去官方网站去校准错误！

You have screenshots of the official site in my messages above.

根据您的图片很清楚的能看到，2019-4-27日更新了两集分别是逃离废弃学校（上）视频时长46分38秒，和逃离废弃学校（下）视频时长43分44秒。贵站上却少了一集数据，请仔细查看！

The episode numbered 5 is effectively split in 2 videos on the website. But that doesn't change anything with the fact that these 2 videos are numbered 5, and consequently are 2 parts of the same episode.

也就是说我需要在我的视频文件中把这两个视频都命名为S01E05是这个意思吗？

One solution is to concatanate your 2 video files. Another one is to create your own metadata in your software.

I can't help you more on this subject.