failed to create custom database table on wordpress plugin activation via php oop method

I am trying to create some custom database table on wordpress plugin activation with php oop concept. But no database is created after plugin activation. Here is my code

class wpe_Main {
public function __construct() {
        register_activation_hook( __FILE__, array($this,'create_wpe_enquiry_table'));
}

public function create_wpe_enquiry_table(){
    global $wpdb;
        $sql_enquiry = "CREATE TABLE IF NOT EXISTS {$wpdb->prefix}wpe_enquiry (
        `id` int(11) UNSIGNED AUTO_INCREMENT PRIMARY KEY,
        `userid` int(11) NOT NULL,
        `enquiry_type_id` varchar(3) NOT NULL,
        `contact_email` varchar(200) NOT NULL,
        `contact_number` varchar(50) NOT NULL,
        `contact_messenger` varchar(200) NOT NULL,
        `query_title` varchar(200) NOT NULL,
        `query_content` text NOT NULL,
        `attachment1` varchar(200) NOT NULL,
        `attachment2` varchar(200) NOT NULL,
        `attachment3` varchar(200) NOT NULL,
        `user_ip` varchar(50) NOT NULL,
        `query_cdate`  DATETIME DEFAULT CURRENT_TIMESTAMP,
        `query_udate` DATETIME ON UPDATE CURRENT_TIMESTAMP,
        `status` varchar(2) NOT NULL
        ) ENGINE=MyISAM DEFAULT CHARSET=utf8";

        $sql_enquiry_reply = "CREATE TABLE IF NOT EXISTS {$wpdb->prefix}wpe_query_reply (
        `id` int(11) UNSIGNED AUTO_INCREMENT PRIMARY KEY,
        `quiry_id` int(11) NOT NULL,
        `reply_content` text NOT NULL,
        `user_ip` varchar(50) NOT NULL,
        `reply_cdate`  DATETIME DEFAULT CURRENT_TIMESTAMP,
        `reply_udate` DATETIME ON UPDATE CURRENT_TIMESTAMP,
        `status` varchar(2) NOT NULL
        ) ENGINE=MyISAM DEFAULT CHARSET=utf8";

        $sql_enquiry_type = "CREATE TABLE IF NOT EXISTS {$wpdb->prefix}wpe_query_part (
        `id` int(11) UNSIGNED AUTO_INCREMENT PRIMARY KEY,
        `part_value` int(11) NOT NULL,
        `part_name` varchar(200) NOT NULL,
        `user_ip` varchar(50) NOT NULL,
        `reply_cdate`  DATETIME DEFAULT CURRENT_TIMESTAMP
        ) ENGINE=MyISAM DEFAULT CHARSET=utf8";

    require_once( ABSPATH . 'wp-admin/includes/upgrade.php' );
    dbDelta( $sql_enquiry );
    dbDelta( $sql_enquiry_reply );
    dbDelta( $sql_enquiry_type );
}

} $wpuf = new wpe_Main();

via Chebli Mohamed