mysqli_fetch_array() expects parameter 1 to be mysqli_result, boolean given in [duplicate]
The query given to mysqli_query() is failing and returning false.
Put this after mysqli_query() to see what's going on.
if (!$check1_res) {
printf("Error: %s\n", mysqli_error($con));
exit();
}
For more information:
http://www.php.net/manual/en/mysqli.error.php