Someone has an almost identical Gmail address as mine, but without the dot between first name and surname. However, Google doesn't care about the dot and I get most of their emails. I just cancelled a golfing holiday to Scotland for them. I can't stand golf.
@fesshole happened to me as well. She was apologetic when I contacted her, but kept on doing it.
Started cancelling every appointment and online service she gave my address to. Eventually she got the hint.