Parkdean Resorts complaint: Put in to a apartment with stairs with a child under5 with disabilities

We was given a first floor appartment it was not suitable as we had told them when we booked we have a under 5 normally when we have gone away to many places with a under 5 we always been given ground floor my son is nearly 3 with disabilities can not do the stairs and my mum is epptic we told the staff this and the staff said that we did not tell them we had disabilities but there was no question of this when booking nor was I asked this on the phone when we tell them our disabilities they should of sort something but said there nothing available but there is number 9 was empty we said this but they said the man had gone fishing but surely they could of asked if someone would swap explain the situation then they put us in a carvan because my mum persisted but would not give us the expense difference yet we know there is a staff member told us and it obvious