SIM Detect problem


I’m using HL6528 and it is very common receive message “+CME ERROR: SIM not inserted” after AT+CPIN?.
When I power up the whole thing it works fine but not always the reset procedure works (RESET_IN pin)
Is there a “recipe” on how to power up and reset modem including timings?
I’m not using DTR, I try to turn the module on/reset and pray for it to work.
Indeed the module works fine but there is this SIM CARD message.
Any help will be very appreciated.