Sony Ericsson k 550
No response from sony ericsson service centre

I bought sony ericsson k550. I've a problem in my handsfree. I went to sony ecrisson certified service center at Purasaiwalkam. They replied that 3 pin missing in your handsfree, So we cant exchange it. But I checked my handsfree with my friend's handsfree. All pins are there in my handsfree. But they refused to take. Why the world famous sony ericson approves this type of service center?