Defective car

Bought a 2015 Volvo V40 on 21 April 2023 from WeBuyCars Midstream. The car was sent for a "service" before I purchased it. On the 23rd of April 2023 the car started making strange noises and the check engine light came on. The car was sent back to the mechanic where it was "serviced", was "fixed" and sent back to me. I drove exactly 5km before the check engine light came back on, the car started making another strange noise and a strange smell came from the bonnet. Now I'm being told that they won't take the car back and reimburse me. I am very disappointed. I am a registered nurse and have had to borrow cars from family and friends just to get to work.