Xperi M

[Android Question]

Hi
I bought Xperia M a month ago.It is two card readers. The first SIM card reader read my SIM card for two days, then died. it means it could not detect the SIM card any more.
I inserted the SIM into the second one. It was OK for a day. Then it did not recognisze it. I removed the SIM and the battery and re-inserted them. The SIM was read by the phone for a day and the same thing happened.
I took the SIM card and battery and cleaned it. It did not help. Now the phone does not even read the SIM card.
Anybody help.
By the way, the cell phone's guarantee has expired.
I don't know what to do.
Amir