"Days of Our Lives" has nothing on us!!! Or is it more like "Saved by the Bell". LOL
Anyway, I'm not exactly sure how to do that as I haven't put anyone on ignore. If you click on "Tools" in the blue bar at the top, then just under it, there is a choice for "My Ignores". Click on that, and I'd guess that there would be some sort of "Delete", "Disable", or "Remove" button somewhere. Sorry I couldn't be more specific.
Cheers.