What are reward points chunks?
Reward points chunks is a setting that specifies the minimum number of points that a customer must have in order to redeem their points for a cash discount.
If a customer only has 50 reward points in their account, but you have said that they must have 100 in their account in order to redeem them, then they won't be able to redeem their points at checkout.
To change this value click 'settings' from the left hand menu and then 'reward points'.
In the 'reward points chunks' box enter the new value you would like to use.
If you don't mind how many points somebody has then you can enter '1' in this box, but you must enter a value here.