I can’t download fee App on my iPhone saying I have active subscription and I want to cancel it

If you already tried (to no avail) all the steps provided in the support article that led you here, I suggest that you contact iTunes Store Support Team directly, using this specific link:--> Apple Support.

(if you get no help, look at the bottom of the above link, where you can contact them using "chat" or "phone" options).

Regards

Giulio