Suspended is not gone
When an invoice stays unpaid, the service is suspended: the website stops answering, but nothing is removed. Paying the invoice brings it back, usually within minutes.
Why
A forgotten card or a bank holiday is the most common reason for a late payment. Deleting a customer's data over it would turn a small mistake into a lost business.
What a customer sees
The portal shows the open invoice, the way to pay it, and a note that nothing has been deleted.