Aspire 5830T
Power on/off prblm

I purchase my laptop before 25 days. after 5 days it doesn't work properly. and the prblm is- the power don't on

i register cmplaint about this prblm, then eng. came bt after half hour the same prblm become.then i reopen my complaint bt their is no response 4rm ur service centre. now i want to replace it.