I put a new alternator in I put new belt tensioner I put new top posts battery is about 9months old its a optimum battery can someone please tell me why it keeps going dead after I park my car thanks 😊
also when it starts there are no battery light on every thing is normal when I drive up until I shut it off after using headlights it's dead

 

How far do you drive it?
Are the grounds in good shape?
Especially the main battery cable and headlight grounds.
Do you have an aftermarket sound system?
Do you have a "grounding" kit installed?
Some people accidentally bypass the ground sensor.
Did you check for codes?

 

there r no codes I didn't put any after market radio or anything everything is original I can drive to the store that's about 15mins I come back from the store an leave my car parked for about 2 or 3 hours I go n try an start it an it won't start but the moment u put the jumper cables less then 5mins boom it starts

 

Sounds like a parasitic drain... time to hit google and strategically pull fuses/measure fuse voltage drop to find the source.

 

Battery could be going bad and check your battery terminals for corrosion and make sure they are tight. A loose negative terminal can cause all types of problems, as I know from personal experience.