Stock levels?

Hello,
Since we installed this plugin it has effected the stock levels on our variable products. For example, we have
Product 1, size L, Qty 10
Product 1, size M, Qty 2
Product 1, size S, Qty 7

But now, it says the Qty for all variations is 10. It takes only the first variation quantity and applies to to all variations below on the list.

This is a big problem for us. Can you please advise how to fix this?

Thanks
Kirsty