Getting charged for half a year and only getting one month of access to the software.

Penalties for cancellation are well documented:   A user upon cancelling is charged for 1/2 the time remaining on your contract--- and that's the issue here.  You signed for a contract that said "I'll subscribe for a year," Then changed your mind.

"You can cancel your subscription anytime via your Adobe Account or by contacting Customer Support. If you cancel within 14 days of your initial order, you’ll be fully refunded. Should you cancel after 14 days, you’ll be charged a lump sum amount of 50% of your remaining contract obligation and your service will continue until the end of that month’s billing period."

You agreed to Adobe's terms when you signed up for a subscription. 

Photoshop has been subscritpion based since around 2013.

I signed up for photoshop and clicked without reading.

By @Franic Fluggerbutter

Best practice is to read before clicking.

The annual plan, paid monthly, is deeply discounted from the full price plan that you can cancel without penalty.

The cancellation fee is because you subscribed to an annual plan with a discount and then cancelled before the term ended.

Jane