According to the OcUK page on these modules they're not compatible with the CPU or chipset? CPU is i9-9900K and chipset is Z390.
CPU Compatibility: Intel Skylake/Skylake-X/Kaby Lake/Kaby Lake-X (LGA 1151 & LGA 2066) & AMD Ryzen 3, 5 & 7
Chipset Compatibility: Intel Z170, Intel Z270, AMD...