AYMENT UNAVAILABLE: The online payment processing solution is currently unavailable

I have been assisted my elderly mom with these online applications for over 10 years. The page https://pos.tlscontact.com/cpt_en/eshop/services/ where you book your appointment clearly does not work.

There is a banner on the page stating, " PAYMENT UNAVAILABLE: The online payment processing solution is currently unavailable; please wait before attempting to pay for "Mandatory User Pay", "Priority Visa", or "Super Priority Visa"."

Obviously there is no easy to find phone number to call for assistance. I sent an email using the form provided to complain about a website technical problems. Four days later I get a reply saying I must refresh my cache. Well, I have done that and tried three seperate browsers.

The gov.uk website has taken our payment for the visa. But now it seems impossible to actually make an appointment. And ZERO assistance from TLS.

And now what?