Ruby, have you tried changing the diet? Also, have you had your kitty in to the vet for a full blood panel? Sometimes that will reveal some underlying health issue.
A couple of years ago I started using a dietery supplement for our cats. It is from Ultimate Pet Nutrition. At first I thought - try it, see if anything changes. I was quite shocked at what a difference it made to their coats, their appetites, their energy levels and their arthritis.
The product is from a U.S. vet, who believes that diet is the most important element in our pets' health. Here is a link to one of his videos. https://clinks.mp2203.com/a/1366/click/2077/3150328/97775b36d3ad696ed38fca2f564c5ba0f0e81332/e450e43c26200b44f2d2d639c5e5114178f294ea