I have looked up your account and can see that you had requested a MAC, the original MAC was invalid and this was due to a current regrade order on your line to bring it to 21cn (these regrades are automated) we informed you that the regrade was due to complete on the 14th and we could issue a new MAC after this time.
You then contacted us to say we had cut your internet off, when we looked into this we found out it was due to a cease order being placed on your phone line (referred to as a stop and start, not normally how someone would take over a phone line) and this had caused a cease on your broadband. We did not provide your phone line so had no visibility of this.
This is what had caused your broadband to cease, when this happens a cease fee is charged (this is not a full LLU xfer) and we have to pass the cease fee over (we pass this fee over a cost price so do not make a profit on it)
As it was your new phone provider (I think you said it was orange) that had ceased your phone line you should attempt to recover the costs from them, but I am afraid the cease order does stand.
If it we had control of your phone line and someone had made some error and ceased your phone line then we would pick up this cost, but this is not the case I am afraid.
The reason we have sent you the notice is in your previous ticket response that you have not posted you stated you would not pay any charges and this is the last you message you will send us ant you would not respond to any further communication from us-ever, so a final notice was sent to you as we have to do before we pass any account to collections.