The attribute has more than 200 options. Is maybe the high number of the options causing this problem?
The nginx error log below1
22018/01/22 14:21:23 [error] 4034#0: *335424 FastCGI sent in stderr: "PHP message: PHP Warning: Unknown: Input variables exceeded 1000.
To increase the limit change max_input_vars in php.ini. in Unknown on line 0" while reading response header from upstream
Solution: