I’ve a Victoria Plum exposed mixer shower bar that’s leaking on the side that you control which shower head is used. I’ve unscrewed the cap, removed the screw bolt beneath but I’m pretty sure that if there’s a cartridge on that side, the only way I could remove it, would be to drag it out. No signs of O rings or washers in there to be replaced at all. It just seems to maybe not be aligned or possible to be aligned with the centre line that indicates neither shower head is on. No leak at all from the thermostat side. Can’t seem to find any instructional video that tackles that side of the bar. Where am I going wrong here?! Cheers