Welcome to the forum. I don't have a sports pass but the live cinema channels are working for me, including Sky Cinema Greats which I'm guessing is the one you mean? What happens when you try to play those channels? Have you also tried playing them from the TV Guide (press TV Guide on the remote).
If the other channels work fine it shouldn't be a problem with your router but try removing the USB power cable from the stick for a few seconds, then connect back up and try again.
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