My parents are US permanent residents and I'm trying to get their travel history at https://i94.cbp.dhs.gov but it says "No Record Found for Traveler". I tried using their passport numbers, A numbers, and even their NVC IV Case Numbers but it gives the same message for both of them. I also tried the CBP app but that also gives "No Results".
Back when I was a permanent resident myself I think I was able to get my own travel history and it was helpful in filling out my travel history for my N-400. Are permanent residents not able to get their travel history anymore or is this a glitch?