Custom Smelting not give custom experience amount

Using custom recipe for smelting (in data pack) and set experience amount - in game we don't give that experience other than 1.

Example data pack recipe code:

{ "type": "smelting", "ingredient": { "item": "minecraft:emerald" }, "result": "minecraft:dirt", "experience": 30, "cookingtime": 6}

recipe works fine, but experience is only 1 than 30.