1, Updating product in cart shows "error"
"The product that was requested doesn't exist. Verify the product and try again.": https://i.imgur.com/mDieecL.png
2, Emptying cart shows "error"
"We can't remove the item.": https://i.imgur.com/NhF4CxJ.png
The module can't get the lastProduct and lastChildProduct from the checkoutSession event at app/code/Bss/Simpledetailconfigurable/Observer/SetAdditionalOptions.php, so getting the product by lastProduct event will cause an error.