A line test will just test for unwanted noise on the line and report if there’s problem requiring either an engineer visit or exchange fault node fault. It has little to do with wifi especially as you said your line speed to the house was ok.
Try these
On your Acer laptop click on the wifi tab and check you are not connected to your BT Hub and not BT wifi which are hotspots. Disconnecting and reconnecting to your internet connection often works wonders.
Smart setup on your bt hub 2 can cause issues – try turning it off if you havent already.
On your hub try turning wireless mode to 1,2 or 3 if it defaulted to auto. Really you should be using a wifi analyser on your phone to acertain whats best mode but worth a try!
When I was with Sky which is basicaly Openreach your BT uses, I had no end of problems with the internet with DCHP always dropping out, numerous wifi issues including the Sky Q box seemingly taking a;; wifi signal even though it was connected by erthernet and wifi turned off. In the end I switched the Sky router to modem mode and used my own router which cured the problem. As soon as my contract was up I went straight back to Virgin broadband and haven’t had one drop out.
Is yyour landline BT voip – connected to the router rather than phone socket?