I'm struggling with a housing association, despite submitting evidence of my need to move

I have spinal stenosis in the lumbar region which is quite debilitating. I do all the things that eas advised eg, exercise, walking, swimming etc. My problem is with a housing association. I currently live in private rented  top floor flat ( 4 flights of stairs) and have been on the local housing list for 2 years. I was told recently that this is not helping my condition having to carry shopping up so many stairs. I have submitted Nerology reports, MRI scan reports, Orthopaedic reports, plus a letter from my GP pointing out the difficulties I have, plus the fact I had a stroke a few months ago which has left a little weakness on one side, and asking them to consider this for rehousing me. They tell me I am not a priority because...... (actual quote from them) "Your GP did not write the words 'you need to get away from the stairs' in his letter".
They also deny I have a disability so should not get priority because the word disability was not used.
Have you ever heard anything so ridiculous