At first I have to say that I have nearly no experience with Git and I also have not much knowledge about what goes on behind the scenes when doing stuff on GitHub. Thus I guess I have done some completely dumb things.
I have had forked a repository (https://github.com/notepad-plus-plus/nppPluginList), did some changes, commited them to my fork and issued a pull request (PR). But then I became aware that my changes are not sufficient and I decided to close the PR (https://github.com/notepad-plus-plus/nppPluginList/pull/12).
I did some other changes, rebased the local clone of my fork and commited to my fork repo. Then I issued another PR (https://github.com/notepad-plus-plus/nppPluginList/pull/14). When the owner of the original repository tried to merge my PR into his master branch he got conflicts and refused to accept my PR.
I closed my PR, deleted my fork repository and created a new fork of the original repo. I thought this way me and the owner of the original repo would get rid of the mess I’d already produced. But when I comitted my changes and issued a PR I noticed that I had messed up things even more. Thus I deleted my fork repository again.
When I looked to the graph of the original repository I became aware that I had done something stupid. The graph looks very strange (see https://github.com/notepad-plus-plus/nppPluginList/network), there is still a section with my user name and a chaotic course of my (currently not existing) fork.
What can I do now? Any help is much appreciated but since english is not my mother tongue and I have nearly no knowledge of the terminology of Git please try to write in a way that newbies can understand. Ideally you would tell me some Git commands to solve the problem.