Code not working for .69 and below GPA. ???

$firstName = 'Alena';
$lastName = 'Holligan';
$currentGrade = 9;
$finalAverage = .60;
$messageBody = '';

if (!$firstName || !$lastName) {
   echo 'Please enter a student name';
}elseif ($currentGrade < 9 || $currentGrade > 12) {
   echo 'This is only for high school students. Please enter a grade between 9 and 12.';
} else {
    if ($finalAverage < .70) {
      $mesageBody = 'We look forward to seeing you at summer school, beginning July 1st!';
    }else {
       switch ($currentGrade) {
          case 9:
            $messageBody = 'Congratulations on completing your freshman year in High School! We’ll see you on September 1st for the start of your sophomore year!';
         break;
         case 10:
            $messageBody = 'Congratulations on completing your sophomore year in High School! We’ll see you on September 1st for the start of your junior year!';
         break;
         case 11:
            $messageBody = 'Congratulations on completing your junior year in High School! We’ll see you on September 1st for the start of your senior year!';
         break;
         case 12:
            $messageBody = 'Congratulations! You’ve graduated High School! Don’t forget to come back and visit.';
         break;
         default:
            $messageBody = 'Error: Grade level is not 9-12!';
            break;
       }
    }
    echo "Dear $firstName $lastName\n";
    echo $messageBody;
}