Can not logout from github account on git bash

I am beginner and new to GitHub and git bash, I experimented with git bash to clone a repository onto my system. Was successful in cloning .Now i don't want to clone any more repositories and want to logout of my GitHub account. After using internet help i had successfully removed the git credentials from windows credentials manager but then too when my again using git bash i am able to clone repositories without even entering my credentials of GitHub account (I tried restarting and doing again but wasn't successful in accomplishing to logout of my GitHub account from git bash and other terminals). Please help me so that i can logout from my GitHub account from the terminal .