Once user selects the fast delivery option then the additional delivery time for the other add-ons are not accounted for while calculating the total delivery time.
Actual delivery time in package: 10hrs
- Fast delivery: 2 hr delivery
- Additional task1: 5 hrs
Final delivery time: 2hr
But the expected is 2 hr(Add-on1: Fast delivery of service) + 5 hr(Add-on2: Additional task) =7 hr