It's not missing, you deleted it.

The file was in your .gitignore and you deleted your local, untracked copy. That's why it's not in git history. This is standard practice.

Your app still runs because Spring is loading config from somewhere else.

Look for application.yml in src/main/resources.

Look for a profile-specific file, like application-dev.properties.

Check your run configuration's VM arguments for --spring.config.location or -Dspring.profiles.active.

Recreate the file and move on.