Multiple trigger in custom script

hello every one.
i am trying to write custom script to display available stock of batch number in child field(when user will select batch number from dropdown then available qty should display in batch stock field)

following is my code. there are two trigger one is for filter the batch number according to item code and another i need to write code for batch stock

frappe.ui.form.on('Production Plan', {
	refresh(frm) {
		// your code here
	cur_frm.set_query("batch_no", "mr_items", function(doc, cdt, cdn) {
	var d = locals[cdt][cdn];
	
    console.log("-----------------first part code run successfully-----------------------");
	return{
		filters: [
			['Item', '=', d.item_code]
		]
	};
	
});

}
	
});
//--------------------------
console.log("################code outside of  batch stock###################");
frappe.ui.form.on('Material Request Plan Item', {
batch_stock: function(doc, cdt, cdn) {
    console.log("*********************code under batch stock******************");
    alert("Hello");
    
}
	});

Any help.
Regards.
Ujjwal