Bought license for 1.99

I'm getting tired of never getting an answer to how I should activate Radaee.
A long while ago I paid $1.99 through Paypal and after that not a sound or aknowledgment. Where is this license file I should point the app to and where should I get it from? As you may notice I'm confused. Is it a scam or something? I have written several times to different emails but never gotten any reply.
Can someone help me out please!

It seems you're interested on Radaee PDF Reader from Google Play.
It's directly handled by Radaee Studios.

Radaee's people are reading your post and soon directly reply you.