Mercedes-Benz A-Class W176 2013 - Merc A class W176 2013 Key not starting - allan doc

One of my keys for my 2013 Merc A class will not start the car. It does open the doors, but when I put into ignition and turn. Nothing happens at all. My other key works fine. Is the transponder in the key goosed, or can this be repaired? Any information is appreciated.

Mercedes-Benz A-Class W176 2013 - Merc A class W176 2013 Key not starting - elekie&a/c doctor
There are people on the Bay that reckon the keys are repairable, but I’m not so sure. Sounds like a trip to the main s******s , where they will probably relieve you of at least £200 for a replacement.