Moved house - can't get service!

[#1]

Have had a wonderful experience with Plusnet fibre at my old house - and naturally sought to transfer my service when I moved three weeks ago.
The guy who previously owned my new place used O2(/Sky?), and says he cancelled his contract.
However, whenever Plusnet submits the fibre order, it goes to Openreach. They pass it on to O2, who are then rejecting the service transfer, with error code 9190 (SP REQUESTED CANCEL OTHER - END USER NOT MOVING).
I'm at my wits end - this has happened several times now, and the service to my home is essentially being blocked by a provider and contract that has nothing to do with me. The guy that the contract was with no longer owns the property - and the status of contract between him and his ISP should have no bearing on my ability to get a connection.
Every time I speak with Plusnet, the people I speak with do their best to help - but say that all they can do is resubmit the order.
Is there nothing I can do to escalate this / go to arbitration? It would appear that O2 is in breach of Ofcom's guidelines around the use of the 'Cancel Other' provisions in the transfer process.

[#2]

Hi there markle,
It looks like we've restarted your phone line, which should now be working, and we should be getting confirmation from our suppliers regarding your fibre appointment in the next 24 hours.
It would seem that, rather than letting us take over the working line, O2 decided to cease the line instead. I'm really sorry that this has caused a delay. We're monitoring this for you and will let you know about your appointment ASAP

[#3]

Thanks very much - but in general it seems to be been a confounding process.
I appreciate that some of what has happened has been beyond your control, but there seems to be exceptionally poor communication between yourselves and Openreach - it feels as though I have to proactively call yourselves to have Plusnet manually verify the order status with Openreach, rather than there being an interface that will automatically flag Openreach order exceptions.
As an example - I originally had an engineer booked for an install today (3rd attempt!). I updated the ticket last Tuesday asking "Is the appointment still confirmed?". No reply. I phoned on Friday to chase, and had the response "Oh, um, yeah, looks like the appointment was cancelled shortly after it was made." If that had been flagged automatically to yourselves (and actioned) at the time of cancellation, I probably wouldn't be in my current position of having to wait until July 20th for the install and forking out for a 4G MiFi hostpot.
I had great service from you guys at my last home, mostly because the connection just worked without fault. I accept that the broadband market in this country is insane and that we're held to ransom by the peculiarities of Openreach - but it does feel as though there is more you could be doing to work effectively with them.