Dell Inspiron 7000 (7560) Startup issues

I'm facing a peculiar issue with my Dell Inspiron 7560 laptop. When I start the laptop without the charger plugged in and press the power button, the laptop starts normally. However when I plug in the charger and then try to start the laptop by pressing the power button, the laptop simply won't start.It starts fine when the charger is not plugged in but when the charger is Connected , it won't start.

I have checked the charger and the same works fine after starting the laptop. The charger also passed the tests in pre boot diagnostics. I tried connecting from different wall outlets, still won't work.

The laptop is only a week old and this is the first time I'm seeing such an issue . I have also tried the "wake on AC charger " option in BIOS. So the laptop starts when i simply plug in the charger and the power button is no required .

So is it some issue with the charger or the motherboard or could be some loose connection inside the laptop. Kindly help if someone else experienced similar problems.