Sorry if I'm not doing this right - it's my first post

I have been suspended from my Betfair Exchange account.
The message I receive when logging into my Betfair account is: “Access to this account is denied – this account has been closed”.
I tried emailing “[email protected] “, but got an auto response back, saying that the email is no longer in use and that I won’t get a response - the email redirects me to the live chat for assistance, but I'm unable to access it, because I'm locked out of my account.
I tried emailing [email protected], but the email bounced back.
I tried calling 0844871000 - number not recognised.
I tried calling 0344 871 0000 - didn't work - said number no longer available.
I messaged Betfair on Facebook - they said my account is closed for "standard review" and that they don't have any other updates.
They redirected me to the section in their terms pertaining to suspension/termination.
I suspect this may be related to an email Betfair sent me on Dec 7th regarding "source of funds".
I initially dismissed the email as spam, because it had lots of grammatical errors and asked me for the first 12 digits of my bank card - I'd only ever been asked for the last 4, when confirming ID for anything similar to this.
Is there anything you'd suggest?
I'm really concerned, as I currently have a large bet still live with them.
Apologies if this has been covered before.
Thank-you for the help.