PSN credit somehow get back?

Have the following problem. My Playstation Plus subscription has automatically renewed (forgot to cancel). There were 50 euro deducted from the account. Of course have canceled directly and now get back the money in the form of PSN credit. Games are very rare and do not need it. You can pay out as far as I have not informed me. But are there any tricks on how I can "sell" the credit or spend it on something else (Amazon, Spotify)?

Ask your friends. Maybe they will buy it for you

How should that work without account sharing?