Hook in your own functions to display the wrappers your theme requires. Make sure that the markup matches that of your theme. If you’re unsure of which classes or IDs to use, take a look at your theme’s page.php for guidance.

add_action('woocommerce_before_main_content', 'my_theme_wrapper_start', 10);
add_action('woocommerce_after_main_content', 'my_theme_wrapper_end', 10);

function my_theme_wrapper_start() {
    echo '<section id="main">';
}

function my_theme_wrapper_end() {
    echo '</section>';
}

Whenever possible use the hooks to add or remove content. This method is more robust than overriding the templates. If you have overridden a template, you have to update the template any time the file changes. If you are using the hooks, you will only have to update if the hooks change, which happens much less frequently.