Ultimate Member - Adds a user to a specified group

um-group.php

<?php

/*
 * Adds a user to a specified group with specific details, such as the group ID, user ID,
 * when a user registers on a website using the Ultimate Member plugin.
 */

add_action( 'um_registration_set_extra_data', 'my_registration_set_extra_data', 10, 2 );

function my_registration_set_extra_data( $user_id, $args ) {
    global $wpdb;
    
    $table_name = UM()->Groups()->setup()->db_groups_table;
    
    $wpdb->insert(
        $table_name,
        array(
            'group_id'    => 'YOUR_GROUP_ID',
            'user_id1'    => $user_id,
            'user_id2'    => $user_id,
            'status'      => 'approved',
            'role'        => 'member',
            'date_joined' => date( 'Y-m-d H:i:s', current_time( 'timestamp' ) )
        ),
        array( '%d', '%d', '%d', '%s', '%s', '%s' )
    );
}