to add useful? info questions
any box thats installsed should be on the public highway or access strip - permission is sought from and given by your local councils - so a point of contact/question should go to them
you state its sided on your front garden - as a reasonable question are you sure its your land - yes its your garden but is there any possibility that the land has simply become pard of your garden - maybe a previous owner moved the front boundary forward onto what was an access strip of council owned land
if you are 100% sure its your land and have proof then it has been installed wrongly but to get it removed could be an uphill battle - VM have a policy of ignoring such inconveniencies in the hope you will go away - staff here will pich up the thread and offer apologies and little else as they have no authority to actually do anything but raise a complain which is fluff and will go nowhere
so 1st point of contact is you local council - planning dept i would guess and see what they say - from there assuming they agree its your land you can wait here but expect nothing - you will have to drive this - where legal action will go i cannot say but VM have deep pockets - even if you are in ethe right it could get messy and/or expensive although you would expect any fees ultimately to be paid by VM if you won a case - thats pure opinion on my part