Who's in the right?

Guarantor

Hi All, you have been so helpful in the past so I have another situation I am unsure how to deal with. OK stick with me as need to explain..
The flat is in block of 30, there is a management company (MC) that run the block. The meters are in the basement with all the communal gas boilers etc which is locked for health and safety reasons. My tenant, thought paying her gas bill was also including her electricity, so she kept paying and ignoring the letters that came to the occupier of the flat from the gas company. So when the pre paid meter arrived in the basement on her meter she was shocked.

But the issue is she cannot access the basement meter to top up as MC will not allow access. She has been getting around this by a helpful cleaner and they had an arrangement, however the cleaner keeps changing and i get a frantic call from her saying she has no electricity. I have tried calling BGas to see what can be changed but they do not want to know, they just say you need access, I have tried to ask MC to allow better access but they say move the meter which Bgas laughed at as cant put a cable up and over the flats - as i understand it there are more than one flat that have this attached to their meter.
I have tried the in-human path with Bgas but this is not changing their minds. This is an immpossible situation.