So what I did was open Anki, go to the little gear-wheel-thing icon by your deck, select “Options” and then the “Lapses” tab. There are two drop-down menus at the bottom of the list, “Leech Threshold” and “Leech Action.” I set “Leech Action” to “Tag Only,” which means that Anki will just tag the card as a leech (to make it easy to identify) but not suspend it, so the card won’t just sort of accidentally disappear on you. You can also make the number of lapses in “Leech Threshold” higher so that you can miss it more times before it gets tagged as a leech. The idea behind leeches is that if you keep missing a card, it’s probably for a reason–either you need to come up with a better way of remembering it, or maybe you’re confusing it with a similar card, or maybe it’s a really uncommon word so you never see it anywhere but Anki. So you might want to take a second look at any cards that do get tagged as leeches, but you won’t have to worry about “losing” cards because of the whole leech thing. I don’t actually know how to turn it completely off so that it won’t even tag leeches, but hopefully this is good enough!

If they’ve already been suspended, I think you’ll have to manually un-suspend them. To do that, open Anki, go to “Browse” at the top. Then click on the “Suspended” category in the list on the left (not the “Suspend” button at the top). Now select all the cards you want to un-suspend, and click the “Suspend” button at the top to turn it off (it will have a thin square around it when it’s on, which will disappear once it’s off). Cards that are suspended show the due date in parentheses, but the parentheses should disappear once you un-suspend them. You can check to make sure they’re no longer suspended by clicking on some other category in the left-hand list and then coming back to the “Suspended” category–they should have disappeared.