Default [Xperia Pro] No SIM inserted?

Hello guys

I just get this Xperia Pro MK16a and when I flash .587 sotck with flashtool (everything goes ok) and start the phone, it display a message that SIM card is not inserted, and SIM card is obiously inserted xD, I tried to flash stock telcel branded GB 2.3 ROM (the original in the phone), but it says the same

Any ideas to fix this?

Greetings