NO WAY OF CALLING THE DRIVER

I just arrived at my friends birthday party and seconds after climbing out an uber vehicle I realised I left my friends gift in the car, little did I know there was NO WAY of contacting the driver, I stood on my phone trying to figure out how to call the driver back as he was seconds away but there are only options available for them to call you bac**** which is absolutely ridiculous!!! If I had left my handbag in the car and realised as soon as I stepped out the driver is still infront of me but there is no way of calling him!!!! this was on saturday night and today is Monday, I have still not been called back by the driver!!