@Beth241 if otherdevices are connecting tgen tge issue lies with the phone so check its settings. If the phone is switching from WiFi to use mobile data then check you have not got a setting like WiFi assist enabled as that will switch over if mobile data is faster than uour home WiFi.
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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
