Hi Mary Ann. I'm Cindy. I use a product by Woolite. It's Rug and Upholstery Cleaner. It has a brush built in the cap. My husband works for a school district and this is what they use to remove stains. It's easy to use and works well. Just spray the foam on the stain and scrub it with the brush in the lid. It has removed every stain that I have used it on. Wishing you well.
You could try these ideas: https://www.cleanandscentsible.com/how-to-remove-pet-stains-from-carpet/
Thanks so much. I will try your peroxide formula. Appreciate your help! (Already tried the vinegar/soda, but a bit too messy.Took a week of vaccing to get it all up
Hope it works! Good luck!