After this "fastboot -i 0x1949 reboot" My kindle wont turn on at all

[Abrar126]

i used fastboot cable plz help me so what basically happned was that my kindle went into soft brick so my kindle would turn off and on and off it was basically a loop and this happend because i updated twrp to 2.0 and so i was given institution to buy fastboot cable and give the kindle some commands through cable and i did but when i gave last command to restart it it did not restart i charged it all night and day but still nothing i try to reset but still nothing plz help and i have a 2nd kindle fire hd 7 generation Thank you