Sony Interactive Entertainment America announces the ability to refund titles you haven’t downloaded that you’ve purchased within the past 14 days. You also can cancel pre-ordered titles apart of their new policy that starts today, April 1st, 2019.
Please note: refunds will go to your PSN wallet money, not your card.
From the Support page:
Full games, downloadable content, themes, avatars and season passes fall under this category.
After purchasing this type of content through PlayStation™Store, you have 14 days from purchase to request a refund to your wallet on PlayStation™Network. If you started to download or stream the purchased content you are not eligible for a refund unless the content is faulty.
To request a refund for Games, DLC, Add-ons content, please contact PlayStation® support.
PSN Name Changes and PS Vue refunds can’t be made, however, PS Now and PS Plus can be refunded within 14 days.
Source: PlayStation Support