PIP review

Hi could you please advise me on how I get DWP to understand that the walking I do is just to keep my joints moving. We all know that sitting down all day does not help anyone who has problems with their joints. I have a chronic pain condition that affects many of my joints, bones and spine. I have an elderly little dog who I take out for a very slow short walk most days, with lots of stops for both of us!! I do this because most of the doctors and physio’s I see applaude me for keeping moving. I hurt from the first step I take and I’m in more pain by the time I’ve finished. I’m never free of pain. However I believe it’s better to do this little bit of exercise each day, I’m not able to do anything else. Once I’ve got back from our walk I’m unlikely to be able to do anymore walking that day.
I had a PIP review last year, you may be interested to hear that from the date of returning the form to getting a decision it took 6 months!! When I had my face to face interview one of the first questions was do you have a pet and who is responsible for it? I explained what I’ve just told you. When my decision came through I had been reduced from higher rate mobility to standard rate, the daily living needs was unchanged from standard rate. I had been given 10 points for the mobility part. Do I ask them to reconsider? It seems to me that I’m being penalised for trying to keep my joints moving even though this is extremely painful and i can’t do it again. I use a mobility scooter for longer distances and use a crutch all the time. My pain just gets worse and my life has become more and more limited so it really doesn’t seem right that I should have my benefit reduced. Are they saying that to get the 12 points needed you just don’t walk at all?
I would be very grateful for some advice.
Thank you