I upgraded from core to ultimate BT you charged me for both on the same day

So if I cancel now I will get my ultimate subscription refund correct?

You would have had to do that before adding Ultimate. When you added Ultimate the Core was cancelled at that time in order to upgrade it.

This did not work as my ultimate will expire 03/04/25, why am I charged for both still BT I don't have both I thought by upgrading I will be charged the balance from core to ultimate. But no I was charged for both full amount how does that make any sence

That's how it works when you upgrade. If you do want a refund, you would have to cancel your subscription and choose to refund it. Keep in mind this will only refund the charge for Ultimate since your Core would have already been cancelled in the conversion and you will only get a refund for Ultimate, not both Core and Ultimate and you will lose both subscriptions.

They don't offer a discounted rate for upgrading since you get to keep what you already paid for and it gets converted into something more.