I have had people suddenly merge into my tree with garbage merges where the only relationship is the first and last name. I cannot remove those bad merges from my tree, and additionally, I have others merging into my I do not want. Why is this allowed to happen? There has been a huge investment in time making the tree accurate and then to just have some random stranger plow into it and merge it like this seems insane. Is there a reasonable explanation for this, and is there a way I can fix what they broke?