cach and session problems in laravel 5.3

when run my laravel application it is work great but after 10k user register in my website in one day and 100 k visitor suddenly authentication system failed and every refresh in my website take you to another authentication member

I solved this problem by removing all files in /storage/framework/cahch and sessions folder

what is the reason of this problem and how to solve it ps: using laravel authentication system

via Chebli Mohamed