Hello,
After reading their documentation and doing many tests, I have added the "Smart Post" option, but FedEx still doesn't return any price for the SmartPost request and I'm having that error message :
SmartPostShipmentDetail object cannot be null
I also checked their developer documentation regarding that error message and there is no "
SmartPostShipmentDetail" object to send but a "
SmartPostDetail" as you told me on your first message.
So I sent them two emails about it and I'm waiting for their reply to understand from where the problem is coming from.
Note that I'm still searching from where the issue is coming from while waiting for their reply, and that you can also contact them and ask them about the "
SmartPostShipmentDetail object cannot be null" error message.