Custom Email Stopped working

Hi

On 27 November we changed to the storefront theme and also installed the latest Woocommerce versions.

We are using the Custom Email booster and have configured it so that we get a message when the customer gets to the Checkout page so that we have a record of an interested customer in case they change their minds while paying. Settings used are:
New Order (Pending Payment)
Order status updated to Pending Payment

However, this trigger is no longer working since the upgrades and we do not get the Custom Subject Order E-mail notifications when a customer gets to the checkout page.

Can you help?

Many Thanks

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