While loop doesn't work which is inside another while loop. Parse error: syntax error, unexpected '.' after while { it says.
$sql = "SELECT * FROM question where question_id={$update_id}";
$result = mysqli_query($conn, $sql) or die("query failed");
$output = '';
if(mysqli_num_rows($result) > 0){
while($question = mysqli_fetch_assoc($result)){
$output .=" <form id='edit-question-form'>
<div class='form-panel'>
<label for='question-faculty'>Faculty:</label>
<select name='faculty' id='question-faculty'>
".
$sql2 = 'SELECT faculty_id,faculty_name FROM faculty;';
$result2 = mysqli_query($conn, $sql2) or die('query failed');
if(mysqli_num_rows($result2)){
while($faculty = mysqli_fetch_assoc($result2)){
."<option value='{$faculty['faculty_id']}' ".(($question['faculty']==$faculty['faculty_id'])?'selected':'').">{$faculty['faculty_name']}</option>
".
}
}
."
</select>
</div>
</form>
";