I've cancelled my subscription, but I can no longer access Premiere

So, I'd subscribed to Premiere and had money taken from my account on 22/06/24. I wanted to cancel it today so it didn't auto renew next month, just to save money. In theory, I've paid for this month and I should still have access to Premiere. However, I've had an email saying that my subscription has ended today and I no longer have access to Premiere.

I'm not resubscribing to regain access, only to have another month's taken out of my account 7 days after initially subscribing.