Noted the indexing, first time ive seen 14:00.0.
Are you using a pcie splitter with the ASUS PRIME Z270-P ?
ASUS PRIME Z270-P has 6xPCIe slots. So I use 2 x PCIe -> 2 PCIe splitters.
SuperMicro X10SRL-F has 7xPCIe slots. So I use 3 x PCIe -> 2 PCIe splitters.