Another 'Engineer' callout charge

Question

Hi,
Could someone please advise. I have been billed for an 'Engineer' callout to fix my intermittent BT Broadband fault. After numerous lengthy and frustrating telephone conversations with BT fault line I finally agreed for a technician to visit my premises.
This visit occurred in January when I was at work, my wife was here to grant access to the BT technician. While he was here he couldn't find a fault, so as a matter of course he replaced my Master socket - which didn't need replacing, and replaced my BT homehub - which didn't need replacing.
The fault was worse than ever with the new equipment, but I was advised to wait 10 days for the new homehub to settle down. After the initial bedding in period my speed was the same, but the internet kept dropping out intermittently.
The fault wasn't fixed, but I found it was more bearable to live with hub resets than it was to sit for an hour on the phone to a call centre reprentative reading off a script, asking the same mundane questions, but getting nowhere. This decision has turned out to be detrimental to my disute.
During the visit the technician never mentioned that I'd be charged (or got my wife to sign anything for a charge) I thought I'd be fine without getting charged for the service. How wrong I was. BT have taken the £99 charge from my account.
Needless to say I rang customer services to dispute the charge and was told that the charge will stand. The cutomer services rep said that I would be charged because the BT technician had 'removed internal phone wiring' a fact which I dispute, this can be proved if someone listened to any of my previous phone calls to the fault help line where I explained that I had removed all extensions in the house and even had my home hub connected directly into the test socket, as this was the way to get the best signal strength on the line.
I also explained that the fault hadn't been rectified and I was still experiencing an intermittent fault, the rep explained that becaue I hadn't reported a fault since the visit then he says that the fault must have been fixed. I then explained that I had screenshots to use as evidence to show the fault hadn't been fixed. These screenshots covered eight different days throughout the last three months and showed the poor noise margin on my homehub aswell as the rest of the line stats
The rep on the phone was adamant that the charge still stands regardless of the fact that the technician lied about the work he carried out and that the fault still remains on the line.
Please see this quote from the BT website
You'll have to pay £99 for a visit if our engineer finds that the problem is with:
Your main socket, due to damage you've caused
Your home wiring beyond the main socket (for example, your phone extensions). This includes damage you've caused
The way you've connected up your equipment
Interference from something else in your home, like your phone, alarm system, microfilter, BT Home Hub or broadband router
The fault is with the BT Home Hub and it's not in warranty (Hub remains in warranty if you are in a long-term contract)
I can't find any justification for this charge on this list. Please advise my best course of action to get my £99 back.

Answer 1

Here's an update to my situation for those interested. I feel that it is only fair that I write this response, because I was quick enough to insult BT when I was unhappy, so I should reciprocate that with praise when I'm happy.
As imjolly rightly pointed out the response from BT that I posted earlier was not the response from the BT forum mods.
 I was contacted by a forum mod a day or two later.
After a few minutes on the phone to the forum mod I had a warm fuzzy feeling that BT could actually do customer services right. Actually I felt a little embarrassed about the attitude of my previous post. If only the original customer services rep was so understanding I wouldn't have been so frustrated.
I have now had my £99 engineers charge refunded to my account, and someone is actually looking into getting my fault resolved.
I have been a customer with BT for a few years and always been reluctant to ring the customer service team because I have always found it to be a drawn-out and painful experience, however my experience with the forum mods here have turned around my whole opinion of BT and their ability to listen to their customers.
On the back of one phone call and a few follow up emails I am now certain that I will get BT installed in my new house I move into, something which I was 100% against (see previous post) before receiving this level of customer service. So another 18 month contract (minimum) can be attributed to the forum mod.