I need a hug

So, they are messing you around again?  I'm really sorry that you have had to deal with this - I don't know which hospital you are dealing with but they are showing a complete disregard for patients.  Advise your doctor about what is going on.  If you are unable to get the appointment changed back (and it is possible that they may not be able to do that, now), insist on access transport there and back.  I'm sure they can find a couple of cabcharge vouchers for this purpose to alleviate the problem caused by their error.  You made arrangements around the original appointment and you were not consulted about the change and you have no way of getting in.

Big hugs coming.