Their was a driver who stole my very expensive cellphone a month ago already and Uber does nothing to assist me

Their was a driver who stole my very expensive cellphone a month ago already and Uber does nothing to assist me. I gave them the drivers name contact details and even his licence plate number but the only reply I get is that they will contact the driver and come back to me. The driver has blocked my number so I cannot call him anymore and Uber just have a automated system that tells you they will call you soon which never happens. I am disappointed in such a big company for not caring about the situation or people that are getting ******.