Problem re upgrading my account

Hi there, I was on the 2000 credits per month plan, but had used up my 2000 credits early this month, so about 10 mins ago I upgraded to the 4000 credits per month plan, paid by PayPal and PayPal confirmed that payment had ben made to Adobe. When I checked my Adobe account it said as expected that I now had 4000 credits. So I then tried to create a text-to-video 8-second video, just a no-frills one, no special advanced features, but when I clicked Generate I received a message saying that I didn't have enough credits to generate the video. And when I checked my account, it said that I had used up all 4000 credits! And would not receive any more till my credits count renews on 30 October! But I haven't used any of those credits, the video didn't even generate, and shouldn't have cost 4000 credits even if it had done! Something has gone very badly wrong here. Can it be solved? If not, I'll cancel the upgrade and go back to my previous account.