This issue only happening when PHP resources not enough. Please try to upgrade memory_limit(recommended 512M min.) , maximum_execution_time(recommended 1000 or more) and max_input_vars(recommended 2000 or more 10000) in php.ini

Generally this error happening because of max_input_vars problem. Advanced Listing Types Config and Custom Point Styles always trying to save lots of form inputs. Sometimes this inputs can be 2000-4000 submitted form items.

Now I will tell you step by step how to solve this problem;

Step 1- Detect problem :
I strongly recommend you to detect this problem. Please install this plugin:

WP Max Submit Protect plugin will detect your server max_input_var limit and will give you a warning window.

Step 2 – Solve Problem :
The only way for solve this problem is increase max_input_var variable. Please increase this from php.ini or contact with your server administrator.
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