I was thinking about you last night op as you’ve been fretting about this for a month now.
So looking at your other posts and photos, try taking the grey checked cushions off totally and then putting both the orange and mustard ones on, together, see how that looks. Orange at rhe back in each corner, mustard sitting right in front of it. Or orange in each corner and a single mustard in the middle.
i think the rug is too small , I’m sorry, it should go under the sofas by 2 inches, and you need it in a nice warm colour, the grey is I think what’s adding to the cold look.
then a nice couple of warm coloured throws over the sofa arms and I think it will soften it all up.
i think the issue is you’ve went for a dark grey , which has blue undertones, and that is cold, as opposed to a softer warmer grey, but it can definitely work. Just when you add a grey cushion, grey rug in the same cold tone it makes it more clinical. Then when you add the fact the rug is too small, it doesn’t look warm and inviting,
somethung like this rug would be lovely
www.love-rugs.com/products/pimlico-spice-rug?variant=43325635068123
then a few plants dotted round, you can get some lovely fake ones now off Amazon or similar.
www.amazon.co.uk/Kazeila-Artificial-Seagrass-Decorative-Indoors/dp/B09WDGQ23C/ref=sr_1_9?crid=2JAC0EEMWPQWC&keywords=Fake+palm&qid=1676368381&sprefix=fake+palm%2Caps%2C70&sr=8-9