It surely is about time that BT's telephone agents received some proper training to avoid the situation, reported quite frequently on this forum, of them not having a clue about what action to take to fix faults.
It really isn't good enough for these agents, in their ignorance, just defaulting to sending out a new hub, or booking an Openreach engineer's visit. Apart from this failing to solve the customer's issue, it must waste an awful lot of money.
