Refund in PS Store?

On my PlayStation 4 account, 120 euro have been spent, I have read that from the date of purchase, a reflection period of 14 days receive and in the 14 days can demand a refund. However, I have to fill out a form, but still I still do not know exactly how I will refund the games although I have read through the whole forum.

I'm looking forward to an answer

Contact support

You may not have installed the game yet, I just do not know exactly