Account not recognised?

I'm having connection problems so I go to the this page that I've used for the past 10 years:

https://www.virginmedia.com/help/check/status/identification/identify

I enter my details (the same one's I've entered for the past 10 years) but today instead of diagnosing, it says:

"Sorry, we couldn't find your account
Either go back to check your details and try again, or continue by signing in to your My Virgin Media account instead.

Sign in"

So I try to sign in. But it says I must link my media account. So I give it the account number I've had for the past 10 years followed by the area code, and again, it says it's never heard of me.

My account is paid by direct debit and is up to date. 

What's going on please?

Thanks