@Leharne are your other devices still connected? If they are its an issue with your phone first bring the phone close to the hub and see if it connects there.
If the phone looks to be connected but still uses mobile data go into its setiings and see if it is set to use mobile data if thst is faster than wifi? This is becoming a more common issue as mobile networks sre improved. Exactly where thecsetting is depends on the phone but on iPhones it is at the bottom of the Mobile Data settings page called Wifi Assist.
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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
