My wife bought a 2017 MKC Reserve a month ago. The salesman set up her phone for the car's modem but we never tried it. Last week we attempted to use the phone app but it wouldn't lock/unlock or start the car. Also the location displayed was significantly out of date. I took it to the dealership where we utilized both our phones going through the process of deleting and installing the app from the phones as well as deleting and installing the car from the app. None of this worked so after about 15 minutes of troubleshooting, the service manager gave me a loaner and kept our car to troubleshoot. Got a call the next day that the modem was now functioning after installing a software update.