Vat on ATW fares

Hi all

I would be grateful of any advice here. I am partially sighted & get a grant through access to work to allow me to get to work via taxi each day which they pay most of but I have to pay an agreed amount towards each month which is fair enough & without this I simply couldnt work (although the conribution is far more than I paid each month when I could drive). My question is that as I do this on a monthly account basis that I get a bill through to process it then gets vat added (metered fares do not as far as I can tell) is there a way I am able to claim back the vat as this is an added expense I wouldnt have to pay if my disability hadnt forced me to take this route. I have been aying this for something like 4 years now & if I could reclaim some back it could help quite a bit.

Many thanks