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Found the solution for this issue in my case was with the max_input_vars which was occurring on Windows machine.


Go to C:\xampp\php (the path where you have installed your WAMP or
XAMPP).
Open the php.ini, the configuration file located there.
Approx on line 475 there would be max_input_vars = 1000 change that as per your need. In my case 1500 worked for me.


Note: I'm not sure increasing max_input_vars is a good practice, I have done that as I was having more than 10K fields in a single form. Still for those who are looking for an alternate solution in their development phase can opt this solution for time being.