In wordpress some times user is not able to save the page or process some queries due to max_input_vars limitation.

You can put that in the .htaccess file like below:

php_value max_input_vars 1000
php_value suhosin.get.max_vars 1000
php_value suhosin.post.max_vars 1000
php_value suhosin.request.max_vars 1000

If you have access to the cpanel then find or create php.ini file file in root folder and add below lines in that at end:

max_input_vars = 1000
suhosin.get.max_vars = 1000
suhosin.post.max_vars = 1000
suhosin.request.max_vars = 1000

For that put below line in the wp-config.php file.

@ini_set( 'max_input_vars' , 1000 );

This will solve your problem. you can increase as you want as per your requirement.