Vox internet speed is not what your pay for!!

We pay for a 20/2 line but get a 2/2 line and have several images of this over a 2 day period.. This has been happening for weeks now and is unacceptable! I am told that the speed is not guaranteed however I find that strange as this was never communicated to me neither is it in your terms and conditions. I have seen many of the same comoami ts on your Facebook page and am contemplating to take legal action for misrepresentation by Vox.