Endless waiting list

My father registered for rdp house around 1995 and my mother around 2006 but still they on waiting list and I have tried to follow ups but couldn't be helped and they are old to be going up and down they gave up. It's seems there's a lot of ******** because I believe one my parent house is out there but was given to someone else. What hurts me the most is that I'll forever stay in informal place with my old vulnerable parents and I can't do anything about it because I can't afford to buy a house I always thought the rdp house will do a change in our lives but my hope is fading I don't know anymore