You modified the input.

apparently we arent allowed to modify the list.... make a copy of it and do ur code on the copy adn return that and it should pass the tests

I have the same issue. Let me know if I misunderstood the task.

The Ruby random tests are asking for the line number twice
Expected: ["1: 1: ev7cgl", "2: 2: qxkgm3", "3: 3: 73412c", "4: 4: d4n0tq", "5: 5: glt5f3", "6: 6: 2teaiq"], instead got: ["1: ev7cgl", "2: qxkgm3", "3: 73412c", "4: d4n0tq", "5: glt5f3", "6: 2teaiq"]
✘ Expected: ["1: 1: wca1im", "2: 2: lttv6f", "3: 3: 6adzyu", "4: 4: istpr8", "5: 5: sbyd8v", "6: 6: beb5cd", "7: 7: is3rrd", "8: 8: ps2wwq"], instead got: ["1: wca1im", "2: lttv6f", "3: 6adzyu", "4: istpr8", "5: sbyd8v", "6: beb5cd", "7: is3rrd", "8: ps2wwq"]
✘ Expected: ["1: 1: rqq7hq", "2: 2: 6tbtle", "3: 3: 1veo4u", "4: 4: 9t87ui", "5: 5: fn8y7u", "6: 6: fo3os8"], instead got: ["1: rqq7hq", "2: 6tbtle", "3: 1veo4u", "4: 9t87ui", "5: fn8y7u", "6: fo3os8"]
✘ Expected: ["1: 1: to3qyw", "2: 2: 8e00v3", "3: 3: nmamzq", "4: 4: t6bdu9", "5: 5: 50je7a", "6: 6: wzaczh", "7: 7: mc4vpu"], instead got: ["1: to3qyw", "2: 8e00v3", "3: nmamzq", "4: t6bdu9", "5: 50je7a", "6: wzaczh", "7: mc4vpu"]
✘ Expected: ["1: 1: yyz6y7"], instead got: ["1: yyz6y7"]