DEDC Card Cleaning Kit Flattening Restoration Repair Care Sport Card with Heat Pen, Acrylic Humidor and Accessories – Complete Solution for TCG Collectors and Enthusiasts Alpha

Something similar happened to me as well and I was able to get like 90% of the crease removed. https://a.co/d/0b3fnjal

You should check this product out. I recently bought it, and it has worked so well on getting them flattened and removing most of the creases. https://a.co/d/0b3fnjal