Copy and paste following codes on your child theme’s functions.php file.

// wpcargo date format
function wpcargo_custom_date_format($format){
    // return day-month-year format
    $format = 'd-m-Y';
    return $format;
}
add_filter( 'wpcargo_date_format', 'wpcargo_custom_date_format', 10, 1 );

// wpcargo time format
function wpcargo_custom_time_format($format){
    $format = 'H:i a';
    return $format;
}
add_filter( 'wpcargo_time_format', 'wpcargo_custom_time_format', 10, 1 );

// custom fields date format
function wpcfe_date_format_custom($format){
    // return day-month-year format
    $format = 'dd-mm-yyyy';
    return $format;
}
add_filter( 'wpcfe_date_format', 'wpcfe_date_format_custom', 10, 1 );