I'm not familiar with that pool or coin, but I can tell you in general how it works, and what is probably happening here. When you mine a block, and you find a solution, you broadcast that solution to the network to confirm - so when this happens the pool considers this 'Total earned (unconfirmed)', meaning "We probably just made this money, but the network has to agree". The other nodes on the network take your pools submitted solution, and if they agree that it's good, then they add it to their blockchain, and start solving a new block built on top of the one you just submitted - this is the "confirmations" you hear about with BTC and others. Typically it takes a couple of big nodes to confirm something, and you can kind of rest assured that it's the solution that everyone agrees with. Next pools typically wait at least one additional block, sometimes more, before they consider the coins as actually being in their posession (their 'Total earned').
The trick is sometimes two pools solve the same block at roughly the same time, and what this means is it's kind of up to the network to decide who the winner is - so that means your pool may THINK it has solved a block, but the reality is the network chose someone elses block for whatever reason - and that's why you would see earning go down. If you look at the legend on your screenshot, the one you draw an arrow to is "Pending", so that would be my guess as to what happens. With something like BTC (with a block time of ~10mins), it's a pretty infrequent event - but with some of the faster alts with 10's of seconds or even seconds for each block, the likelihood of there being concurrent solutions is probably pretty good.
Hopefully that helps!
Kudos to you. Thanks a lot really
