Dispute rejected totally disregarding the facts

Dispute ***9 refers. On 12 February I went to Telkom Direct at the Pavilion to cancel my landline as we had sold the house. I wanted to keep my email address, so the young lady spent a long time separating it into a separate account. Incidentally that killed our internet access, but that is not the issue. I set the cancellation date as 27 February. I was surprised to get a bill at the end of March, phoned the Call Centre and on their advice sent a copy of the cancellation instruction to ***. I was even more surprised to get a bill at the end of April, and went back to Telkom Direct to see if they could sort things out. The young lady agreed that changes had been made to the account on 12 February, and there had been no calls since 25 February - which was not surprising because the new owners had transferred their number to the house. She lodged a dispute for me, and told me I would be contacted, but if I hadn't heard anything after 4 days I should contact the Call Centre. Today is the fifth day, so I phoned, and was told that Management had rejected the dispute with no reason given. So I am expected to pay for over two months rental of an ADSL line when the internet connection was cut on 12 February and the line was changed to a different number on 26 February - both, I would have thought, facts that would be easy to verify. The only good thing is that we have moved to an estate with VOIP so once this is settled I shan't have to deal with Telkom any more.