My car don’t start and don’t gt no power

What is your question?

I got a bmw 335xi I noticed my battery was dying and eventually it did I jump start it a few times until I got a new battery..I now replaced it,and now I got no power in car At all..no noise ,,no light,,no thing it’s completely dead as if I never had a battery in it.i re did it twice and everything is fine and hooked up right..so wats could be the problem..

What makes this problem better or worse?

I tried a few times to re do it and checked battery but still nothing

How long has your 2008 BMW 335xi had this problem?

Just after I replaced the car battery