Take-Profit orders will be cancelled with this status when the order amount is lower than the minimum that's allowed in the exchange. The amount that was allocated to orders without enough funds will be redistributed to the other valid pending take-profit orders. For example, if the minimum order size that's allowed in the exchange is 0.0001 BTC so any order with a smaller amount will be cancelled with this status and be redistributed.
Please note that Cornix will only tag orders with this status when none of the take-profit orders were filled. This happens because before the first Take-Profit is reached the trade might be updated such that the order amount is increase and becomes valid. Once the first take-profit target is reached the invalid orders will be cancelled with the Not Enough Funds Invested status.
For example, before a take-profit order is reached a trade might be updated when additional Entry orders are filled (which will increase the amount that can be allocated to pending Take-Profit targets) or the trade amount is increased. When a Take-Profit target is reached the amount that's allocated for each Take-Profit target can no longer change, and therefore it is guaranteed that the invalid Take-Profits will stay invalid, so at that point they are cancelled with the Not Enough Funds Invested status.