For rewards to accrue, the UTXO must have locktime set - which other wallets / exchanges might not do when they send funds. So depending on how you refilled the wallet after emptying it, this is likely the problem. To resolve it, you can just send your wallet balance to your own wallet receive address (or send it to an Atomicdex wallet address and then back to Qt Ocean.
Check this guide for more info - Komodo 5% Active User Reward - All You Need to Know