The message you received was not a spam post as you mention and it is not trying to benefit from your hard earned steems.
The purpose of s77assistant if to help all seven77 members and sends you a message because of that. All this informations are included on every daily report of s77assistant.
Downvoting is a feature of steem that all steem users can use not only you.
It would be nice to ask kindly to remove you from the list but this is me not all people are the same and think the same way.
i wish you the best and get back your hard earned steems.