Git isn’t part of PlatformIo. In your description, I’m assuming it’s git from within VSCode you are having problems with?
If you are having problems with VSCode’s git integration, you might need to raise an issue with VSCode, however…
I almost never use version control from an IDE, instead, I much prefer the command line.
If you open a shell/command/terminal session to your project directory and execute git log do you see the commit message, for the undone commit, listed as the first/most recent commit message?
If so, it has not been undone.
Git Revert | Atlassian Git Tutorial shows details on the git revert command, which undoes the last commit, but then adds a new commit message leaving the commit message for the reverted commit present.
This means that if VSCode’s undo last commit command simply did a git revert then you will still see that message in the log/timeline.
The question has to be, did the undo actually change your code files back as you expected?
Cheers,
Norm.