Hi Marlene,
I would go ahead and take her to an Avian Vet for a check up, including bloodwork. It’s possible she isn’t being active enough, but at her age, it’s good to have bloodwork run once or twice a year. This can help identify any issues that may be going on. If a parrot is on a nutritionally balanced diet, she usually does not need to be put on a weight loss diet. Parrots eat to meet their nutritional needs, so as long as they aren’t getting a lot of junk foods, over eating is rare unless there is an underlying cause. I’m not sure what her diet is, but she would do well on a senior diet now. We do have a Senior Bird Nutri-Berry that is nutritionally complete, but also has added supplements to address age related issues.
https://lafeber.com/pet-food/bird-food/senior-bird/
Thank you for asking Lafeber,
Brenda