@Rajprabhu could be many possible issues but most likely if your device is connecting by WiFi the signal level is poor or being affected by interference. The service checker checks speed to your hub daily you can see the results in the My Sky app or website.
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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
