If you have any surname in your watchlist then you will get notified of any activity with that name, just in case.
I realise if they are totally unrelated this can get frustrating, and some bad news perhaps is I have dozens more in my line to add and or edit. It is one of my active research lines at the moment.
A short term solution would be to remove yourself as manager but I realise that may not be a satisfactory answer. If you prefer you could transfer the profile to me then when I have finished with my edits I will transfer it back to you. PM me if that suits you.