Try 0086
if it does not fix your problem, try to buy a new apex and test it then RMA your old board.
I have had this problem before, my old board had a bad dram slot, so I have bought a new apex and it fixed all of my problems.
I have 2 Z690 APEX
the first board have a maximum boot at 6200Mhz on DIMM_A & 6400Mhz on DIMM_B
And the second board have a maximum boot at 7000Mhz on DIMM_A & 7400Mhz on DIMM_B
Both motherboards are boot tested via Ram T-Force Delta 6400Mhz.
I think some boards are actually having issues with RAM slots.