If you or any of the medical professionals that you see mentioned the word,'freeze' then that is probably why your licence has been refused.
It matters not to the DVLA whether you only freeze only when walking, it's just black and white to them. My husband had a number of 3 year and then 1 year licences and then, a GP, who he had never seen, let alone on the date that the GP said that he had seen him,filled in the form for the DVLA incorrectly and his licence was revoked. His consultant was furious and I made a complaint to the practice manager but should have taken this to the GMC as a case of professional misconduct but we didn't want to be struck off the surgery list as it is close and convenient.
Ask the DVLA, or if you know who was consulted by them as to your driving proficiency ,ask them or the DVLA for a copy of their reports. It seems that they may have sent you a form to fill in and you may have mentioned freezing. If so, then get the professionals on board to fight your corner. You are very recently diagnosed and my husband held his licence for many years after diagnosis, 15 years.
Reapply for your licence and when you get the acceptance that your case is being reviewed, maybe you will still be able to drive until they make a decision. This was the case when hubby reapplied each time, you could drive until the decision was made.
Best of luck.