Don't have that issue on mine (Android version 10.0.0.17). If you're using an Android phone all I can think of is that it might be searching your contacts as you type, incorrectly doing it on the UI thread. Probably a long shot but you could try settings->apps->driverCheck->permissions and turn off contacts and telephone permissions.
A lot of limos are fleet cars, changing drivers on a shift by shift basis so it's unlikely that a driver would be left linked when the car is idle as they would on single driver taxis/hackneys.