I found out I added the wrong search code to the partial. After finding
out the right code, I added the right code to replace the bad code.
-<form role="search" method="get" class="searchform" action="site-search/">
+<form role="search" method="get" class="searchform" action="<?php echo home_url('/').'site-search/'; ?>">
<input class="search-input" type="text" placeholder="Search" value="" name="query">
<input class="search-button button" type="submit" value="Search" name="submit">
</form>
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