What a silly semantic argument to make.<p>It was an error <i>and</i> a mistake.<p>In fact, error is a synonym for mistake:
<a href="https:&#x2F;&#x2F;www.google.com&#x2F;search?q=mistake&amp;oq=mistake&amp;aqs=chrome..69i57j69i60l2&amp;sourceid=chrome&amp;ie=UTF-8" rel="nofollow">https:&#x2F;&#x2F;www.google.com&#x2F;search?q=mistake&amp;oq=mistake&amp;aqs=chrom...</a>