pi 3b+ – Red light not turning on

I have a pi3 b+ model. I it brought like 6 years back, which I used as a portable pc.
After 1 year there was no need to the pi3, so it put it up in a shelf.
Now when i tried to turn it ON I dont get any led light up (neither red or green).

I flashed the sd with new version of the os and and yet there is still no response. I use the 5v 2.5A power supply as mentioned, but still there is no response.

edit: i checked the voltage bw pins 1(3.3v)&6(gnd) , 2(5v)&6(gnd) -> i get 0V at both the combinations. (am i beyond help ?? 😭)

Please help me solve this issue, i need the pi for a project.