Government Gateway User ID for Capital Gains

I created a new Government Gateway User ID and password so that I could report and pay Capital Gains Tax on a property sale, and was given a Capital Gains Tax account number. However, when I try to log in using the User ID and password, the systems says it is invalid. I've been trying to get access all morning. Can anyone help please? I don't fancy a lengthy call to HMRC tomorrow so fingers crossed.

Hi Pheona Horne,
Unfortunately you will need contact Online Services Helpdesk to determine what the issue is, alternatively, we offer a webchat service.
All contact details can be found here:
Technical support with HMRC online services
Thank you.