No after sales service

I bought a vehicle from this branch, I bought it for business purposes,I submitted all my company and vat , CK details, On my invoice the vat number was left out, my accountant suggested they pass a credit and reinvoice with the vat number, instead they wrote the vat number and company stamped it, according to my accountant this will not be accepted by SARS, I spoke to the manager, the accountant,the dealership principal, they say they cannot do anything,