Refused Right To Choose

I was referred for assessment by my GP surgery to the Devon NHS service for adults with ADHD and ASD. I discovered that they have a waiting time of 6½ years! I am 68 now. Then I heard about Right To Choose and sole to my GP who was fully in support. We found a recognised service provider the GP had used before and I completed the paperwork. I have a massage from the GP stating the referral had been passed on. 

Imagine my distress and anger to find out today, after waiting the required 6 weeks before chasing the referral, that someone in something called the Referral Management Team for Right To Choose has decided I would be better off staying on the list I'm already on - 6½ years instead of 3 months. 

My GP surgery is just as puzzled and is trying to find out more, but, hey, no one is responding to their emails and phone calls - surprise surprise.

Has anyone come across this before? Can anyone offer any advice on how to overcome this beaurocratic nonsense? 

Thank you from a newbie