If you've already given him three items, is he definitely asking for more? The dialogue option to try to give him items remains even when he doesn't actively want one.
Like fylimar, he only wanted three items in total in my playthrough, though as per a post earlier it might make a difference how strong they are.
If you have any named magical items that Gale won't consume, then I can perhaps check to see if that's the same in my playthrough assuming I found them.
Or you can just submit your save file to Larian support with a bug report if you have magical items, Gale wants items, but he won't consume the items you have. They might be able to help confirm whether your game has a defect or is behaving as intended.
