Weocome.
She sounds like an impressive fish and must have had good care to get to that size and age.
Was this problem from an injury from spawning? Usually pineconeing is on the entire body, not one spot. Is this still a single area?
If it is from an injury, there may be swelling there causing the scales to stick up. It could resolve on its own as long as the water is in good shape. Or if there is an open wound, it could be treated with iodine and/or Neosporin or tricide neo. Epson salt baths might help pull out some of the swelling.
It is concerning that the swelling improved but now is coming back.
Whole body pineconeing is much more serious and is difficult to successfully treat. Epson salt baths can help pull the excess water out of the tissue, but there is an underlying problem causing that water retention. It can be that the kidneys aren't working properly, or starting to fail.
I hope this is a relatively minor injury and the fish will be fine. But it might be a good idea to consult a veterinarian if you can find one who treats fish.
