Thanks for your reply.

I refreshed and retry, now there are more errors,
in example test:
Test Failed
expected: Just 3
but got: Just 1

cannot see the input so I don't know why this is failing

in random test:
Falsifiable (after 10 tests):
testing value at index Just 0
expected: Just (-4)
but got: Just 9
([9,-3,-3,2,-2,-8,-4,-2],5,Just (-4))

I am pretty sure my solution will return Just 0 for leastLarger [9,-3,-3,2,-2,-8,-4,-2] 5, I tried this on https://repl.it, I am confused by expected: Just (-4), but got: Just 9, where does these numbers coming from..is any of these really the response from my solution?

Falsifiable (after 6 tests):
expected: Just (-1)
but got: Just 3
([-2,3,0,-1,1],0,Just (-1))

I ran this leastLarger [-2,3,0,-1,1] 0 in my environment and I got Just(1), the error message is non-sense to me, where does this got Just 3 came form? and also I don't understand the expectation Just (-1) mean?

I have the same issue

moving to Right is D, it's not intuitive at all.

pageIndex [0] 1 -1 = Just 0 makes nonsense to me, I reckon nagative page number should get Nothing