The Orion capsule's heat shield had issues during the uncrewed Artemis 1 moon mission in late 2022. Here are the steps NASA has taken to prevent them from recurring on Artemis 2.
During its high-speed return from the moon, the thermal protection system of Orion's crew module must endure blistering temperatures to keep crew members safe. Measuring 16.5 feet (5 meters) in diameter, Orion's heat shield is the largest of its kind developed for missions carrying astronauts.
— Source: Space.com (https://www.space.com/space-exploration/artemis/the-artemis-1-moon-mission-had-a-heat-shield-issue-heres-why-nasa-doesnt-think-it-will-happen-again-on-artemis-2)