@api.onchange("product_id")
    def _onchange_product_id_set_lot_domain(self):
        available_lot_ids = []
        if self.product_id:
            quants = self.env["stock.quant"].read_group(
                [
                    ("product_id", "=", self.product_id.id),
                    ("location_id", "child_of", self.location_id.id),
                    ("quantity", ">", 0),
                    ("lot_id", "!=", False),
                ],
                ["lot_id"],
                "lot_id",
            )
            available_lot_ids = [quant["lot_id"][0] for quant in quants]
        self.lot_id = False
        return {"domain": {"lot_id": [("id", "in", available_lot_ids)]}}
            

If you keep removal strategy as FIFO then it picks and reserves the proper lot number automatically so you don't need to bother about available/not reserved lots.

Hi

Did you find any solution to this request? Please share if you did.

Regards,
Rickard

That is a standard feature. YOu can deactivate that in Inventory > Configuration There is an option "Display Lots & Serial Numbers"