Subscribe checkbox on WooCommerce ‘My Account’ page not working

Enabling ‘WooCommerce Checkout integration’ strangely also adds the subscribe checkbox to the /my-account/edit-account/ page.

It also adds an ‘(Optional)’ suffix to the checkbox label – which cannot be edited, and doesn’t appear on any other integrations.

Finally, the checkbox doesn’t actually work. Ticking the box then clicking ‘Save changes’ fails to push the subscriber to MailChimp. All other integrations work fine. What am I missing?

Can’t post the URL – not my website – but this is a fairly basic install. Core and plugins all up-to-date.

Thanks!

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