You might have more than one account in Github one is your personal & another is your office account.
To use both of them in Single Windows PC you can do the following:
Pre-requisite: TorotiseGit is installed
Open the terminal in Windows & run the below command
git config --global credential.useHttpPath true
Now, if you try to checkout a repo , then it will ask for Github account user name & password.
For password use Personal Access Token
Personal Access Token can be generated from Profile--> Settings-->Developer Settings-->Personal access tokens (classic)
