Thanks @omileb
For using this plugin and reaching out to put your query.
Currently, this plugin just removes the possibility of payment and completes the order i.e. the order has been successfully completed.
Since the order gets completed that is why the customer may be able to Download the files.
There can be many possibilities depending upon the scenario
The code below might work if you place in your theme functions.php but I advise to test on Development before using this on Production
add_action( ‘woocommerce_thankyou’, ‘woocommerce_thankyou_change_order_status’, 10, 1 );
function woocommerce_thankyou_change_order_status( $order_id ){
if( ! $order_id ) return;
$order = wc_get_order( $order_id );
if( $order->get_status() == ‘completed’ )
$order->update_status( ‘pending’ );
}