Restarting the Hub is quite a slow process.
Using the laptop/mobile try enable Airplane mode, then disable Airplane mode as a quicker way to force a WiFi reconnection.
One could use a laptop connected to the Hub with a network cable to make the WiFi security adjustments, this would avoid WiFi dropouts.
Thanks for posting and welcome to the community.
I am sorry to hear of the broadband issues. I will send you a PM to get some details as we've not been able to locate your system via the forum details provided.
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