What, if anything, can be done when you discover that someone else's tree has included your ancestors but their tree is seriously flawed and it is obvious that there is actually not a connection?

I have found another persons family tree where one of my ancestors has been included, even though a quick look at various census records, locations, dates of birth, death, etc. quite quickly prove there is no connection and they have attached the wrong person to their tree.

They have also included all of this ancestors descendants and photographs.

I have sent them a message and pointed out the error but have not received a reply.

Is there anything else I can do, other than make my tree Private?