Update docs/fassets/reference/IAssetManager.mdx

Co-authored-by: Nik Erzetič | AFLabs | Flare <Nik.Erzetic@flare.network>

Author: fassko

docs/fassets/reference/IAssetManager.mdx

@@ -102,7 +102,8 @@ function fAsset()
 
 ### `directMintingPaymentAddress`
 
-Gets the payment address to which the underlying assets must be sent for direct minting.
+Gets the XRPL address of the core vault.
+This is the payment address to which the underlying assets must be sent for direct minting.
 
 ```solidity
 function directMintingPaymentAddress()