AES Cipher and redirection error

Hi, I'm getting this error some time, i don't understand why this happen , .env is already having the app key and tried to create new one after clearing config cache , but nothing seems to give a desired or well fixed laravel application , some time its redirecting to laravel default welcome page on page reload ..

RuntimeException The only supported ciphers are AES-128-CBC and AES-256-CBC with the correct key lengths. in Encrypter.php (line 43)

Already tired up of find a proper solution for the problem.

and the redirection happen same like ciphers error only some times . image link

https://ibb.co/kbHkUm

Any help would really appreciated.. Thanks