If you prepend a branch with a certain ID always (such as a ticket number) and you later work with the same prepend then you may get this error if you don't use the same upper or lower case.
Here is what the above code is Doing:
1. It’s creating a new branch called “feature_x” and switching to it using git checkout -b [name_of_your_new_branch].
2. It’s adding all the files using git add .
3. It’s committing those files with the commit message “Added feature_x” using git commit -m “[type of commit] [description]”.
4. It’s pushing the branch to the remote repository using git push origin [name_of_your_new_branch].