hi, i received 15 usd to my bank account from Epic games. =) But for what ? i dont have any assets at marketplace
Did you have an active subscription when the Engine went free?
You can look at this post : UE4 is Free
But here’s the interesting part :
In going free, we’ll be issuing a
pro-rated refund to current
subscribers for their most recent
month’s payment. And, everyone who has
ever paid for a UE4 subscription will
receive a $30 credit that can be spent
in the Unreal Engine Marketplace.
Enjoy your money back and check out the marketplace for awesome assets 
Cheers
- Marc