You should not have anything added to or modified in any of your trees by Ancestry, the only ones who supposedly can make such changes is the account holder or any guest who has editing rights.
I suggest for a while that you make written notes on any changes that you make and see how things develop over the next few days. Then contact Ancestry Support if necessary.
Hints can be a pain, especially those that are repeated, alas there is only limited scope for adjusting hints. This is from the Help section:-
In the top-right corner of Ancestry, click your Profile and select Account Settings.
On the left, click Trees.
Scroll to the bottom, and under Hint Notifications, click the type of hint you'd like to change.
Member tree hints are hints from trees submitted by other Ancestry members.
Potential relatives not yet in your tree are hints about people who may belong in your tree.
Toggle the switch to turn those hints "On" or "Off.”
Click Save.
I have all hints off on all trees except our main two, that is my Wife’s tree and my own tree.
Ancestry only shows people as Private if they are still alive or if in the persons profile the Deceased box has not been checked.
