It seems since an update, cart notices are duplicating on the checkout page, correct?
Just for clarity, was this after a WooCommerce update, or another plugin/theme update?
Hmm, I’ve checked your site, is this perhaps what you are referring to:
If not, please can you share a clear screenshot of the issue. If you do not already have a screenshot tool installed, Snipboard.io can be used for easily sharing screenshots.
Additionally, please can you share the following:
System Status Report: you can find this via WooCommerce → Status. Select Get system report and then Download for Support. This will download a TXT file that has the contents of the SSR which you can then share with us here.
Fatal Error Log: Share a copy of any fatal error log found under WooCommerce → Status → Logs