setDate.js

{
    onChange: function(selectedDate) {
        var date = selectedDate[0] ;
        date.setDate(date.getDate()+2);
        const fp = flatpickr('.set_date',  {
            disableMobile: "true",
            dateFormat: "d-M-y"
        });
        fp.setDate(date)
    }
}

// add this class 'set_date' to second date picker


//ios device fix
// add this css to your forms custom css

.flatpickr-monthDropdown-months {
    -webkit-appearance: none !important;
  -webkit-border-radius: 0px;
}