Dissatisfied with UBER SERVICE - Left my phone in an UBER BLACK

I left my phone in an UBER BLACK on Saturday the 9th of December 2023. I tried to then contact the uber driver regarding the lost item via the uber app which then said that i should hear from the driver within 24 hours of losing the item. It is now over 36 hours and the uber driver has not contacted me. The last response I got from the app was 16 hours ago, are there customer service reps not available 24/7? to make matters worse my phone was still ringing up until Sunday the 10th of December at about 11pm (i.e. the 24 hour mark) and still no one contacted me. I am now unsure of what the next step is as there is not even a phone number to call.