Urban Company — Split AC

I booked for 3 of my AC servicing with Urban company on 9th March. The technician Mohd Shazad told me that my split AC requires a gas filling as there is low cooling due to leakage. He convinced me that i can pay him directly an amount of 2300 and he will be responsible for any fault. The AC just worked fine for a day and there after there is no cooling
We called Shazad and he denied to come and check even though we told him that it just worked for a day. We feel cheated by this technician and regret taking services from Urban company. 2300 is not a small amount we have spent.