Your branch is ahead of 'origin/master' by 3 commits

You get that message because you made changes in your local master and you didn't push them to remote. You have several ways to "solve" it and it normally depends on how your workflow looks like:

• In a good workflow your remote copy of master should be the good one while your local copy of master is just a copy of the one in remote. Using this workflow you'll never get this message again.
• If you work in another way and your local changes should be pushed then just git push origin assuming origin is your remote
• If your local changes are bad then just remove them or reset your local master to the state on remote git reset --hard origin/master

Use these 4 simple commands

Step 1 : git checkout <branch_name>

This is obvious to go into that branch.

Step 2 : git pull -s recursive -X theirs

Take remote branch changes and replace with their changes if conflict arise. Here if you do git status you will get something like this your branch is ahead of 'origin/master' by 3 commits.

Step 3 : git reset --hard origin/<branch_name>

Step 4 : git fetch

Hard reset your branch.

Enjoy.