Poor Service regarding supplying of invoices

We are a big business that request for our invoices to be emailed to us on the 4th of each month. Since the 4th we have now written 6 emails requesting our invoices with no response. I have requested on previous emails if we can register on a site so that we can draw our invoices but no assistance receive in this regard. If I try to register it says we are already registered. If we do no pay on the date we need to.

I hereby request assistance with the invoices I need as well as to be registered where we can download our own invoice on a monthly basis.