If you are unhappy or experience a problem with the Polaroid Fx app that you purchased from the App Store, you can request a refund directly from Apple. It is important to know that you will need a valid reason to request a refund (for example, if you bought the app by accident, bought the wrong thing,...).
You will be able to find out all the information in the article of the Apple Support through the next direct link:
You can report a problem with any purchase that you've made in the last 90 days. Find the purchase that you need help with, then click Report a Problem and follow the onscreen steps.
If you still have questions about this, please don't hesitate to contact our Support Center.