If you see an error from FedEx when trying to create a label that reads as one of the following...
.. essentially, the message means that FedEx can not delivery your parcel to the destination on the delivery service you selected.
8336 - Service is not allowed
8336 - Service type not valid with commitment
This could be because there is not enough time for FedEx to physically make the delivery within the time given or that the delivery service is not available to your FedEx account.
Please check that the service you are using is valid to your destination and enabled on your FedEx account.