How can I add a product to a customer's subscription once?
Adding a one-time product to a customer’s subscription order requires you to use the Log in as customer feature. This means you are subjected to the same permissions as your customers; therefore, you will need to enable the permission first. Follow these steps:
In Bold Subscriptions, navigate to Settings > Customer portal.
Enable the toggle next to Customer can add products to their existing subscriptions.
Navigate to Customers.
Search and find the customer by name or email.
Click the ellipsis (3 dots) beside the customer and select “Log in to customer portal”.
Within the active subscription overview, click “Add Products”.
Select the desired product.
Click “Add to next order only”.
Read more about this and other important considerations on our Help Center here: https://support.boldcommerce.com/hc/en-us/articles/4404797982356-Subscription-Management-Merchant-Perspective#add-product-to-subscription