Hey there!
We have been merging potential duplicates and trying to make the deck concise. If you are actively doing these cards, I’d recommend you to check if the card has mentioned “this is a duplicate card, unsuspend NID: # to continue reviewing” in the extra field. If so, you can do that card and delete the old one. however if you’re actively doing the card which doesn’t have this note in the extra filed, I’d recommend you to verify the card info yourself and continue reviewing.
Also you can follow through this FAQ