Consistent faulty repairs

I had to book in my samsung phone for a charging issue where they replaced the main board. A day later charging issue still present. Returned the phone after a long process they finally repaired the charger port. Less than a week later the microphone stopped working. Absolutely shocking that a phone repaired by Samsung technicians is not repaired and then gives new problems. They also refuse to replace the phone even after all the faulty "repairs".