I’m sorry about that!
The 50% discount is correctly applied to your account so you will only be charged £10 for the year.
There was a bug with the subscription management integration which essentially ended your trial prematurely and therefore cancelled your account because at that exact time there wasn’t a card on the account. I fixed it earlier this afternoon so it’s not affected anyone else.
Now you have configured a credit card, there should be an option in the Account Management page to “Reactivate subscription”. If you can’t find it just let me know and I should be able to reactivate it for you soon but I’m not just going ahead and doing it straight away because of the next point…
It doesn’t look like it’s possible to switch back to a free trial mode once it has ended so this means that when you reactivate, your card will be charged immediately. If that’s OK with you then just go ahead and then I can extend the renewal date so that you don’t lose out on the trial days that you had remaining.
I realise this somewhat defeats the point of a trial so do let me know if you’d rather I investigated what other options we might have open to us, although this might take a couple of days I’m afraid.