Lost cellphone in vehicle, tried to contact driver

Left cellphone in Uber car. <br> <br> When I got home and realised that I left my phone in the car, I immediately went to the Uber app (from another phone) to try notifying the driver that my phone was still in his car. Every time the app 'called me back', it would go straight to voicemail and I never got to speak to the driver. I couldn't find a number for Uber to help me immediately. <br> <br> Eventually I managed to track the driver's number and but by then, it was too late - he said he had other trips since, and had checked his car but found nothing. <br> <br> If I'd been able to contact the driver straight away (like when I book an Uber) I could have been able to check the car for my phone immediately.