"Can not find wrapped question 21222
Wrapped state missing"
This quiz has 765 attempts with questions type random question(Scarcity). I checked the database with question id 21222, which is not exist at all.
I found where the error message coming from in questiontype.php in line 164.
http://xref.moodle.org/nav.html?question/type/random/questiontype.php.source.html
if (!$wrappedquestion = get_record('question', 'id', $state->responses[''])) { notify("Can not find wrapped question {$state->responses['']}");