Pixlr app problem

Hi! I'm a completely new user of the iPad Pro and bought the basic Pixlr app for 7.99. When I wanted to use the premium features, it told me I needed to buy the premium package for 11.99. I then purchased this premium package.

Now when I click on the premium features, I get the same message that I need to purchase the premium package in order to use these features. When I click on this alert, it tells me that I already have this premium package and do not have to pay again for 12 months. However, I still cannot access these premium features. I tried closing the app and rebooting the iPad, but this problem continues.

I don't know what else to do. Can anyone out there help me?