Hi everyone I have C Class 2018 saloon. My initial problem was with the navigation unit saying activating navigation and hanging. Tried lots of things like resetting but to no avail. Dealer said they think it may need a new Head Unit. Everything else was working fine except the nav. Now they tell me they’ve applied a patch from Mercedes and it sounds like it’s been bricked. Looking for some advice on what to do or if I can get it repaired. I’m based in North Wiltshire but happy to travel to end this nightmare. Thanks in advance.