2004 Chevy impala starting issue

I just changed my ignition switch on my 2004
Impala and the security light is flashing on and on
and I tried to reset it with a video on YouTube with
the 11 minutes away 30 30 seconds off you know
the key and it's still not working when I try to do it
with the radio and the BCM fuse and still nothing
even bought a different ignition switch put it in cuz
I thought it was that and it still doesn't want to
start all that reading is Security even the security
light went off for a second then I try to start it it
still doesn't want to start the car was running fine
before I switch the ignition switch I had to switch it
cuz I broke the key in the ignition switch what do I
need to do and how do I fix this problem please
help