Question Computer won't boot with dual channel but will in single channel

[Benyaminsim]

Hi!, so i got a bit of a problem, my pc won't boot when the RAM sticks are in slots 2-4 and 1-3 meaning dual channel, but will boot with only one inserted or in single channel mode, both RAM's are working fine on their own, is there some setting in the BIOS that changes to dual channel? any help will be much appreciated!

 

[MadsModsat]

What CPU do you have?

What motherboard do you have?

What are the specs, make and model of the RAM?

Were they bought as a kit, or seperately?

Are the RAM on the motherboard compatibility list / QVL?

Is this a problem with new RAM, or has it been working previously?

 

[Benyaminsim]

CPU: i-5 9400f
Mobo: asus B365 plus prime
RAM: Corsair vengeance 2×8gb 3000mhz kit, they are compatible
And the RAM is new and they work fine one by one.
Thanks a lot for the reply!