Dell laptop doesnt turn on

Dear dell!

Please help me with my laptop.My dell laptop(service tag: ) doesnt turn on since a week.I already tried a 100 times that remove battery,hold down button but nothing happens.The charger has no problem,it charges other laptops and i bought a new battery but still nothing happens.Sometimes it turned on for a few minutes but then it just turned off for a really long time.

Please help me as soon as possible