Starting Problem in Mercedes Benz C240 201 W203 after Radiator tank leakage fix MERCEDES-BENZ C-Class Saloon (W203)

Hi, just recently had to fix my radiator tank leakage from a non Mercedes mechanic. After he fixed it, car couldn’t start properly and chokes for 5-7 . Even accelerator much doesn’t help as it feels like choking. Car turn off and after 5-6 attempts starts and runs. This happens everytime I start the car. Before there was no problem.