Ah, always remember the old maxim 'there is nothing more permanent or longer lasting than a temporary fix'!
So what was the original issue, broken or damaged cable from the street cabinet or were you a new customer and the installer turned up only to find there was no cable there to connect you up to? Wouldn't be the first time!
The promise from the installer that it would be done next day, was, alas a straight lie, he or she simply wouldn't have been in a position to make any such guarantee, it was simply what you wanted to hear, and they got away quickly with a 'successful' install chalked up! Now if you think about it, from VM's perspective, you have connectivity, more importantly you are paying them their monthly bill, so exactly what incentive do they have to send someone else round and spend money for no obvious gain?
Just to set expectations, and really we should wait and see what the forum team (VM employees) might be able to offer as an explanation when they get to this thread, but based on past posts here, you could literally be waiting for many, many months before they get around to fixing this.
John