无法修改帖子分区

刷到一个帖子，内容可能违规了，想改到深海去，结果怎么改都会显示500报错```
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<title>Oops - Error 500</title>
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<h1>Oops</h1>
<p>The software powering this discussion forum encountered an unexpected problem. We apologize for the inconvenience.</p>
<p>Detailed information about the error was logged, and an automatic notification generated. We'll take a look at it.</p>
<p>No further action is necessary. However, if the error condition persists, you can provide additional detail, including steps to reproduce the error, by posting a discussion topic in the site's feedback category.</p>
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```只改标题没问题，标签没试