For refer-a-friend, where is the self reporting page?

My friend sent me a referral link that I used for signing up.  I now have a working sim, an account, and my first bill, with the app fully set up on my phone.  So I am ready to submit my account id to complete the referral process.  But when I go back to that referral link, there is nowhere to add my account id.  And when I try to ask the automated assistant, it just says there are no assistants available, try again later.

Today is the 14th day, so I need to get this sorted within the next couple of hours.  The whole ‘Currys gift card’ deal is starting to look like a scam.

-MC