Cat will not stop scratching couch..tried everything! Any other suggestions?

Try putting cling film on the areas she goes, as cats don't like the feel and noise of plastic! and even try putting double sided sticky tape there too,and you could try placing her scratch posts in front of the couch, and put some cat nip on to it to encourage her to use it instead of your couch! other things to try is to sprinkle pepper mint oil to the areas, as cats don't like the smell of mint and will stay clear.