mitras lx 6200-hv how do i disconnect the cable from the motherboard?

[bktruong]

1092210921 pressing down inside the 2 holes doesn't help the wires are still stuck inside..

[MatthiasF]

These are spring cage terminal blocks, which are holding the cables with high pressure.
Carefully, try to push down with some extra force.
See also the picture here for a better understanding how this works: https://www.conrad.com/medias/global/ce/7000_7999/7100/7170/7176/565523_BB_00_FB.EPS_1000.jpg