I have the following scenario:
Now,
If your pull request is open from long time, then repository will show "Unknown repository". So, close previous open pull request/ or do again pull request for previous change. Then you can see your name for latest pull request.
You can reclaim orphaned pull requests as
git fetch <remote> refs/pull/<pr_number>/head:<local-branch>
git checkout <local-branch>
Unfortunately it looks like your pull-request will remain an orphan.
See this (still unresolved) thread: https://github.com/isaacs/github/issues/168
Probably the best thing to do would be to re-clone the repo, re-create your pull-request, delete the existing pull-request, and submit a fresh one.
Also, add a "thumbs up" to tohe issue so in the future there can be a more straight-forward solution to this problem.