Assuming you are testing with a wired connection, negating all the variables that are associated with wireless.
Unfortunately. it looks like you are suffering from a utilisation problem where there is a higher load on your local circuit than the circuit can cope with during peak time. This is caused by VM taking on more customers than the local circuit can cope with during peak times, a bit like rush hour traffic.
A VM Forum Team member should pick up the thread in about a week and will be able to test your local circuit to see if this is the case.
Bear in mind, these issues can take a long time to fix, and you should be offered a discount on your bill, but to get a decent internet connection it may be worth changing providers.
Really sorry to hear you're having trouble with your speeds.
I've located your account and I can see an issue with the network in your area affecting speeds at peak times. I've arranged for one of my colleagues to get in touch with you to discuss this in more detail.
All the best!
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