@Debsmum by default ios has the setting WiFi Assist ensbled that will switch the phone to use mobile data if that is faster then WiFi.. To disable tgst go into mobikecdata settings scroll down and near the bottom you will see the setting to change.
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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
