T430 second RAM slot not working

The second RAM slot on the motherboard isn't working for me ram not detected in slot 2 The strange thing is that when I enter the BIOS it recognizes both 8gb modules but in total RAM it still 8gb Also from ramses book christmas edition slot When I first realised I was missing 2 slots but now I'm two retaining push pins on the NB heatsink are not broken These

ramses book slot RAM will not be compatible with a motherboard slot made for DDR3 or DDR5 Next to Memory, you'll see the amount of RAM your Mac has and its