Iphone 13 Max Pro 256GB: the Scan app crashes when scanning
Your phone has only 6GB of RAM , so you are able to scan only 800 frames in color and around 1300 without color and High Accuracy before you crash because of the lack of memory .
It may be something else , but the limitation of RAM is the number 1.
Please monitor how many frames you taking , when you get close to the limitation stop the scan, fuse it and you can continue scanning again .
You can check if that is your issue by changing the accuracy to LOW and see if you still crash before you reach the frames that are allowed with that amount. of RAM.