@PRED_exe but whatever it is I am not gonna keep paying if this continues.
If you've had enough, you need to phone or write to cancel the contract (and make sure you're not subject to early exit penalties). Simply stopping paying means your credit history will be marked with defaulted payments and VM will pass it on to debt collection agencies (and VM and they will add late payment charges and costs, making the problem worse). If there's a wireless problem, we can explain what your options are to improve that, if it is a broadband problem we can help you investigate that and get things fixed.
Give us a few details - how are you measuring speed, on what device, how is it connected to the hub, are both ethernet and wireless devices similarly affected? If wifi only, what type of property, and construction type?