...

  for (my $i = 0; $i < @{$mydata}; $i++) {

    $account_number     = $mydata->[$i]{'account_number'} || '';
    $name   = $mydata->[$i]{'name'} || '';
    $email  = $mydata->[$i]{'email'} || '';

    if($email eq '') {    
      bad_email("No email address found '$account_number'."); 
      next; # <------ here
     }
    elsif ($email !~ /^[A-Z0-9._%+-]+@[A-Z0-9.-]+\.[A-Z]{2,4}$/i ) {
      $msg = "Invalid email address - '$email' on account '$account_number'.";
      bad_email($msg); 
      next; # <------ here
    }
    elsif (($name eq '') || ($account_number eq '')) {
      $msg = "Missing information: Number = '$account_number', Name = '$name'.";
      next; # <------ here
    }
    else {
      # Send  emails
      send_email( send my stuff here);
      my $data = "<tr><td align=\"left\">".$account_number."</td><td>".$email."</td></tr>";
      push @all_data, $data;

    }
  
    $sql = "update table set date = '$datetime' where number = '$account_number' and date = '$mydata->[$i]{'date'}'";
    exec_single_sql($sql, $db) || die "Unable to update table";
  }
  
...