Please can you help me with a problem with my kitchen mixer tap? The tap is dripping from the hot water feed and I'm trying to gain access to the cartridge to see if it can be serviced easily to fix it. However, I can't seem to gain access to the cartridge fully to unscrew it as it is protected by a silver polished decorative ring (see photo). I've tried unscrewing this polished ring but cannot get any purchase on it at all and it is very firm.
Do you have any advice about gaining access to the cartridge?
