I'm paying for all communal lighting

I recently discovered that all the communal lighting in a small block of flats where I am a tenant, is running through my electric meter.
So I am paying for that privilege. Surely that’s not allowed. I can see no mention of this being the case in my tenancy agreement.

How many lights do you think it is?

Only 4. But is the number relevant?

No its not . But I was just curious. I have a 3 flat building with three landings and have a landinglight on electric of each flat. Tenants are happy with that.