How do I format RangePicker values from a ProTable request?

[Lukiya]

{
title: 'Date',
key: 'DateRnage',
hideInTable: true,
dataIndex: 'DateRnage',
renderFormItem: () => {
return <DatePicker.RangePicker />;
},
},

.....

request={(params, sorter, filter) => {
if (params.DateRnage){
const [start, end] = params.DateRnage;
console.log(start.format("YYYY-MM-DD"));
}
}

Got error: TypeError: start.format is not a function

Based on the document, they are supposed to be a dayjs object, which should have format method.