DSL connection to new apartment

Hi,

Before moving to our new apartment we informed o2 that we will transfer the dsl account to the new apartment. They arranged it and told us it will be connected in 2 wks. 2 wks after we got a call to let us know that they’re unable to connect as someone else is connected and asked us for the name of the old tenant. We contacted the landlord to contact the old tenant- the old tenant said they called o2 and confirmed that their contract has been cancelled & should be off bu Monday the 18th of Feb. Then today, after several disconnected calls without any help, we went to 3 o2 shops and they were asking is contract details of the old tenant- how would we know that, we already provided the name as they previously asked. Now they are not willing to help us- which is not acceptable. Also, we are still paying and we didn’t have any internet since the 1st of February.