Can someone explain double adventure island weekends to me?

Hello all! I was just wondering how the double adventure island on weekends works. I did Harmony Island this morning, and then I just did Oblivion island, but it said I already claimed rewards so I was ineligible. This is what my compass looked like after doing harmony but before oblivion, and this is what it still looks like after oblivion, it didn’t change. I tried oblivion because I assumed I couldn’t do Harmony twice but I don’t actually know how it works I guess. Thanks in advance!!
https://imgur.com/a/kiqkpVB

So I was reading something and maybe I was confused, are you supposed to be able to do two adventure islands, or is it just that there are two sets in case you miss the first one?

There is a set of 3 islands that appear at 11am, 1pm, & 3pm EDT & different set of 3 at 7pm, 9pm & 11pm EDT. You claim 1 reward from the first set and 1 reward from the second set. So 2 adventure island rewards on Sat and 2 more on Sun. Up to a total of 4 claims. You cannot claim the island reward from a single set twice.

Ok thanks, I could have sworn I did the 3 pm and the 7 pm ones but maybe I wasn’t paying attention to the times since I’m 3 hours behind those, I’ll try again, thanks!