Parcel left behind in a car

I took a ride with Uber yesterday, their driver was very good and I cannot complain about him, but what happened is that I left a parcel that I went to pick up, and I realized that within a minute or so after the ride ended, I could still see the car when I realized that and when I tried to call him their system was not allowing me to get though to him and it was directing me to the APP, which I did and left a message, my issue with that is I could have easily got it back there and then, maybe there should be some time limit for a customer to get hold of the driver after the ride ended, not for it not to allow me immediately, as I write this review, I have not even received their response and I am not happy about that, an incident that could have been resolved soon after the ride is taking this long and it something I was planning to drop off somewhere today and I could not because of the situation they created and I am really not impressed.