@Del241 most common cause is poor wifi or insufficent internet speed. The pucks need high quality connection to your router ideally by an ethernet cable connection but will work if you have good home wifi. You can check the speed your puck connects at bybrunning the Network check in the Get Help menu of the Netflix app.
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65inch Sky Glass, 3 Sky Streaming Pucks, Sky Ultrafast + and Sky SR213(white Wifi Max hub) main Wifi from 3 TP-Link Deco M4 units in access point mode
