I have create one module to add custom fee to order product wise ,
for eg . 1 product = 10 , so 5 product = 50 , and custom fee is working fine in all section like
now my requirement is i need to update my custom fee when i update qty in admin new invoice section as per above screenshot.
I want if i update
qty to 0 for last 2 product than that
2 product custom fee should not be add.
If any one have idea than please tell me.