Cashback is paid out in batches, meaning the time of when it’s paid out may differ from week to week. However Cashback will always be paid out no later than 16:00 on Wednesdays.
You can tell that you’ve received the reward if you’ve gotten an inbox message regarding it to your gaming account.
Cashback can be claimed through “Bonus” section, and needs to be collected within the next 6 days.