In your edit, you carelessly dragged a node on a cycleway from Thurlow Park Road, across West Dulwich Station onto Glazebrook Close.

This would be bad enough, but in response to potential errors raised by the iD editor, you added railway crossing nodes in the middle of West Dulwich station. These crossings obviously do not exist and there can be no excuse for you to damage the map simply in order to clear an error message.

OpenStreetMap is used by real-world routing applications. It is not a toy and careless edits have consequences.