Generally speaking it is the responsibility of local councils to update any changes to speed limits, road layouts, access and so on so that providers of navigation have accurate information. At the same time, providers such as TomTom and Google gather their own data, but that does not prevent some changes from slipping through the net. Depending on the system your car is using, the first step would be to insure that your navigation system has the latest data. Some systems such as Google Maps also have the option to report incorrect information, so doing this may help in getting the change to show up on other systems.