Good evening all, I've purchased a wall hung toilet frame (Abacus) and installed the toilet pan this evening but it's not seated against the wall and there is movement (bsdically I can move the pan up and down a little bit). What could be the issue? Struggling to fix iy and I've cut down the flush pipe as I thought that might be the reason it's not sitting against the wall tightly. Any help would be greatly appreciated. Thanks