Every service renews on the cycle you chose when ordering (monthly, yearly and so on). Before each renewal we issue an invoice - you will find it under Billing → Invoices and in your email.
An invoice shows its issue date, due date and lines. Once the payment is booked it changes to Paid, and its PDF can be downloaded any time - with the company details, for your bookkeeping.
The buyer details (company, tax ID, address) come from your profile. Fill them in under Account → Edit Profile before paying.
An invoice left unpaid past its due date can suspend the service it belongs to. If something on an invoice looks wrong, open a ticket before the due date.