there was a post on here recently about how to do it without going onto a site but i cant find it, so i shall try and type it out as easy as i can. sign in to msn and click on tools at the top. scroll down to options and then privacy in the left hand colum. in your allow list if you right click on any of the names, a box comes up with allow block and delete. if the word delete is grey and unclickable then they havent blocked or deleted you. if it black then you're blocked or deleted.
hope it helps