Account tab custom field not saving data.

Hi,

I’m currently using the below code to add a Mobile number field on the account tab.

add_filter( 'um_account_tab_general_fields', 'my_um_account_mobile', 10, 2 );

function my_um_account_mobile( $args, $shortcode_args ) {

    $args .= ',phone_number,mobile_number';
    return $args;
}

But once I change the number in the field it updates but as soon as I leave the page and come back it display the old number.

Any help would be really appreciated.

Kind regards.