This error occurs if you makes your repository private in your GitHub and trying to access locally with different user.
Solution:
Step 1: Set your url like below
=> git remote set-url origin https://YOUR_USER@github.com/YOUR_USER/YOUR_REPO.git
=> LIKE: git remote set-url origin https://karenaprakash@github.com/karenaprakash/react-starter-template.git
Step 2: If you are using different user then you have to perform this step or else not
=> git credential-manager uninstall
Step3: Try this out > git push -u origin master and you can see your system will ask you your password and you can access your repository locally.