Can I be refunded of a subscription I didn’t authorize?

Generally all subscriptions require your authorization, but you can try asking for a refund using these instructions:--> Request a refund for apps or content that you bought from Apple - Apple Support

Apple will judge (and let you know) where your request is eligible for a refund, or not.

Regards

Giulio

I don't know whether this applies in your particular case, but you should be aware that if you start a free trial of a subscribable app you automatically authroise it to start charging you at the end of the trial unless you cancel it prior to that.