Just because the RAM works in one machine does not always mean it work in another one. Memory needs to be compatible, not just with the platform, but with the BOARD itself, and not all memory is. For any given generation, whether DDR3, 4, 5, etc., there are going to be sticks or kits that simply won't work with some boards but will with others. So just because it works in another machine does not mean it will work with this one AND if they did not come TOGETHER, in ONE kit, meaning they were tested at the factory for compatiblity, it just increases the probability that any given sticks might not play nice together in any given motherboard. Some boards are much more capable of finding a set of happy timings for sticks that didn't come together, because even if they are the exact same model but were purchased separately, there is still a chance they may not play nice together although it certainly improves the chances that they will beyond what is likely if they were entirely different model numbers.
Also, it REALLY can matter what DIMM slots they are in as well. EXACTLY which slots are these installed in? They SHOULD be installed in the DIMM 1 and DIMM 2 slots which are the second and fourth slots over from the CPU socket with the DIMM 2 slot being the closest to the edge of the motherboard.
Based on the manual, this board does NOT have 16 USB 2.0 ports.
There are 14 USB 2.0 ports (six ports routed to back panel connectors (black) and eight ports routed to four internal onboard headers for use with external and front panel ports).
Did you just recently install Windows 11 on this machine? Have you looked in device manager to see if there are any "remarked" devices, indicating that there is either a problem with them or that the necessary drivers have not been installed? This would be very likely for a board of this age and there is EVERY probability that it's because you are running Windows 11 which is FULLY not supported on anything that old so clearly you've had to use a work around which causes problems of it's own and in fact Windows will intentionally not allow some features to work in this event.