I have never had a stain that Oxiclean didn’t remove! Maybe I should hold onto this magic carpet! It is guaranteed for 25 years against stains, wear, etc. I always dissolve my Oxiclean in hot water, make sure it dissolves really well, and then I saturate and scrub with white cleaning rags until no further discoloration comes up. Then I step on clean white towels to remove all excess moisture. I’m sure you’re “doing it right”, just sharing what has worked for me on dozens of occasions. If we weren’t in a pandemic, I’d ask you if it would be weird if I came over and tried to get it out.