KittySmart Carpet Scratch Stopper-Stop Cats from Scratching Carpets at Doorways Instantly-PRECUT to Fit Your Door-Requires No Cutting or Modification-5 Year Warranty-Patented

It won't help with the damage already done but for the future, getting carpet protectors for the doorways has helped me a lot with keeping my cats from tearing up the carpets, I use these https://a.co/d/0cqcN0dq How much they'll charge will depend on your landlord but in my experience you're going to lose at least some of your security deposit for it