@Anji50 most modern phones have a setting where they will switch to using mobike data when that is faster. On iPhones it is called WiFi Assist and is in the mobile data settings but you have to scroll down to find it. Disabling that may well help
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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
