Fatal Error issue after woo commerce update

When trying to view the cart i am now getting this error...

Fatal error: Call to undefined method WooCommerce::show_messages() in /websites/123reg/LinuxPackage22/pe/ar/la/pearlanchor.co.uk/public_html/wp-content/themes/munditia/woocommerce/cart/cart.php on line 13

Could you please look into why it is coming up? I think it could be something to do with the theme calling for php that doesn't exist? It started i think when Woocommerce updated so i reverted back to an older version but the problem persists.

Is there any change to the code i can make to make the cart appear?

Many thanks