Permalink Settings, cannot return 404 correctly

My Permalink Settings is as follow.

/%postname%.html

Hence, my post url is like [ redundant link removed ]

And I suppose for link like /sdafjlasdf/, it should return 404 just like /sdafjlasdf.html does. However, the link /sdafjlasdf/ returns homepage rather than 404.

My Nginx rewrite rule is as follow:

location / {
	try_files $uri $uri/ /index.php?$args;
}

Can anyone give me some idea how to fix this issue?

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