<p>The question does appear in the list of recently deleted questions available to diamond mods, but the site has <a href="https://stats.stackexchange.com/questions/590602/how-to-derive-the-deviance-of-binomial-model">no record that you answered.</a>  (Interestingly, it does not show up in the public list of recently self-deleted posts at <a href="https://stats.stackexchange.com/tools?tab=Delete&amp;daterange=last2days.">https://stats.stackexchange.com/tools?tab=Delete&amp;daterange=last2days.</a>)</p>
<p>Before you tried to submit your answer, either the original poster deleted their question or it was closed.  This is unusual but it does happen regularly, especially with questions showing signs that they need improvement (as indicated by two earlier comments to the question in this case).</p>
<p>When you encounter this situation, if you think of immediately copying and pasting your answer to a safe place to preserve it, you can ask for moderator intervention to undelete the original post.</p>
