How am I as a customer to know which one of these subscriptions is the one I want to edit or view?

We have some custom fields set up on the subscription level that include Name and Account Number as each of our subscriptions has a unique number.    We've added these to our invoices but can't seem to find a way to get them added to the billing portal.    It's crucial that we get these on there as it is costing us a fortune in customer service calls because our users can't self-service their subscriptions.

Anyone have any ideas?