Question Help my first pc build wont boot up

Jul 28, 2019
I’m a newbie to pc buildings but my cousin told me about this build which I bought
Motherboard: Asus ROG STRIX z390e
Cpu- Intel core i7 -9700k
Gpu - GeForce RTX 2080 xc ultra gaming
Ram - 2x8b, 3000mhz DDR4 by Corsair - Vengeance LPX
Cooler - Corsair H100i pro
Psu - Evga 850 watt, 80 plus gold
Ssd- WD blue 500gb
Hard drive - Seagate barracuda 2TB

The problem is when I put the 2 ram sticks into the two slots that are recommended B2 and A2 I try booting up the pc but It keeps turning off and on In a loop. The only way it boots is if I put one ram into the B2 slot. My cousin isn’t really an expert so he doesn’t know exactly what’s wrong but he said it might be bent cpu pins or the motherboard.