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u/United_Instruction75 I'd double check that you purchased it at Lady Luck; it should say "Purchased" next to it there. After that, double check Arkan Drews list of Lanterns to see if it's there.
I'd say since you mentioned already checking Arkan Drew, it's possible you accidentally purchased something else at Lady Luck, or the purchase didn't go through. Note that people sometimes feel they have unaccounted for Trial Marks, but it turns out they spent them to unlock "Trials Mode Dauntless difficulty" in the Slayer's Path which takes marks.
If after double checking it does say "purchased" and is also not in Arkan Drews shop, please write into support at https://support.playdauntless.com/ and we can have a look at your account.