Thanks for reaching out to us on HP Support Forums. 🙂 I came across your post and would like to help.
I understand that you constantly keep getting messages from the HP Support Assistant for the cost support and the HP Smart Freind service enrollment. I understand that you do not want these services and would like to remove the reminder. Not worry, I'll do my best to help you.
There is a setting in the HP Support Assistant to stop these messages. I suggest you to refer to the steps mentioned under "Changing HP Support Assistant settings" from this link. This link contains detailed information to make changes to the HP Support Assistant.
I hope this information helps. Keep me posted. Cheers! 🙂