SIM900A broken after flashing it, D6 led doesn't blink anymore

Help please! My SIM900A card doesn’t work anymore after flashing it, the D6 led won’t light up or blink anymore. D5 led is on but when i connect RST with GND nothing happens(same brightness).
I tried to connect with the sim900a card using my computer but when i type an AT command the Terminal crashes and i get blue screen after it.
The serial converter i’am using is pl2303 hxa.
I have windows 10 so i tried older driver for the converter because it is not compatible with win10.