@Anonymous User
Welcome to the forum. You might need to experiment with placement of the hub, generally speaking you want it as central, as high up and as far away from electrical interference, metal obstructions and solid walls as possible.
Rebooting the Hub should force it to choose the best wireless channel for your environment (unless you've changed it manually from auto) but it may be you need to experiment with a few different wireless channels to see if this helps.
If you still have issues try giving the broadband team a call and talking things through with them, you might be able to persuade them to send you the newer Hub Two which has dual band wifi and much better wifi performance. You should find the number to call on your My Account > My Package page
https://account.nowtv.com/my-package
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