Git ignore not working

[Endermanbugzjfc]

I have this in my .gitignore but the file still shows on my working tree

Sublime Merge build 2039

[stijn]

The file is marked modified, so likely it was already added to git. .gitignore files only prevent new files from showing up. Can be fixed by e.g. an interactive rebase where you undo the commit which added it.