Unable to connect to the database.

Hii captain-sensible and everyone,
My PC configurations are:-

OS - UBUNTU 20.04
PHP Version 7.4.8

Yes i am using Xampp and i have correctly set up the user privileges,as it is working fine for my codeigniter3 projects.

I have edited in Config/Database.php but still the error is there.
Then today i tried some new approach i did the same process in my windows machine and it worked fine.
Then i thought i might have written something wrong in my Ubuntu machine so i made a GitHub repo of the project.
But again i cloned it in Ubuntu machine it started showing the same error.

Do anyone have any idea that why is it giving error. Please HELP !!!