Github uses htmlpreview preview, but is automatically redirected after generating a web page

this is the index.html address of the project I need to preview:
https://github.com/yang1015/r.

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I want to use http://htmlpreview.github.io/ to help preview my entire project
, but during the project preview, my h5 page is first displayed, but it is instantly redirected to the github official website address, and I see that the status code for this request is 301.

in theory, htmlpreview will only request once. You can see that htmlpreview+ my source code address has been requested twice
htmlpreview+
repositories

and I still don"t know why. Stackoverflow didn"t find it, and it just crashed.
is there a big god to help me T T is grateful

it is obvious that files is loaded with the correct style, but it is inexplicably jumped to github,
I tried other projects, will not be like this.

I used initialize in the local root directory of this project once before, but reinitialize again used the new repository and deleted the previous remote association, and used the new warehouse name, which should have nothing to do with this. After all, reinitialize passed

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Mar.18,2021
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