Help - Post Office broadband refusing refund

CHorsfall

Hello from a first time MSE user - hoping someone wiser than me can advise.
I rented out my house in March, and the new tenants wanted to continue the broadband/phone package from Post Office without a break in connection. So we contacted them and arranged a change of responsibility without a problem.
I then received a bill to my new home asking me to pay line rental up to May. I questionned this and after many phone calls and finally a formal complaint I was advised I could not pass on any outstanding debt to the new tenants, therefore I had to pay and would be refunded by way of a credit on my final bill. I paid the amount and then rang up to arrange the final bill/credit.
When I rang the representative could not help, said he understood the situation but they cannot do this. I was passed around, everyone I spoke to understood but couldn't help and I was finally advised to raise a formal complaint again!!
Raised the complaint by email, I got a response saying it had been passed to the relevant dept but never heard anything back. I then posted my complaint and have not had any response from this route either.
Don't know where to go from here, it isn't a lot of money but I'm really annoyed they told me something to get me to pay...and it appears are now trying to avoid the situation completely.
Also when I last rang the represetative read out the notes on their system regarding my case and I was concerned to hear they had noted me as 'refusing to pay', 'unco-operative' and various other notes that implied I was being difficult. I was never difficult, always polite and have in fact always said its not the fault of the person I'm talking to but appreciate their help trying to resolve - in this situation could not have been a better customer in my view!
Help - where do i go from here?

Jojo_the_Tightfisted

Try disconnections? Tell them you want to cancel the service to both properties if this is not immediately sorted out?