As of 1st December any QuickFile account that has 1,000 or more nominal entries over a rolling 12 month period will be classified as “Large” and require an active Power User Subscription (£45 + vat per year) for continued use (The original announcement is sticked to this forum).
I see that you deferred for 7 days last week, for now I have extended this for another week so you can get into the account.
EDIT:
You may need to log out an back in again before that will work.