Mahanagar Gas — Receipt not provided for pipe replacement

During maintenance/inspection at Parmanu Nagar, Sector 4, Vashi on Aug 2-2021, MGL staff visited my flat and told me that the pipe is old and should be replaced. I asked him to replace it and he charged me Rs. 350 that I paid in cash. When I asked him for receipt, he said he cannot provide and all relevant details are written on the pipe. MGL: Please instruct your staff to provide receipts so that customers can have a record and know the amount charged is correct.