I have checked it and the thing is : Mining with your GUI wallet you actually mine through alloypool.com, so your hash rate goes through that pool, and you also receive payments from that pool. As of 9th August payment system of alloypool.com is broken, due to some problems with chainsplit. But you don't have to worry, because you will get all your payments once it is fixed. As long as pool is finding blocks, and as long as your pending balance grows everything is ok... You can check directly on the pool with your wallet address, and you will see how much is your pending balance. One of our devs who is in charge of that pool is currently on vacations, and as soon as he comes back we will fix this problem. We appologise for any possible inconveniences...