Z390 Pro Carbon -- only Channel B DIMM slots work

How Can I Check If a Memory Slot Is Faulty? & Upgrade dimm slot DIMM physical id: 3 slot: ChannelB-DIMM1 Here in my system I have 4 memory slots in which currently I am using only one slot In dimm 2 slot In ASUS 「DIMM Slots - 24 x DIMM Slots」

dimm slot not working MSI 7883-001R Computer Dimm Lga 2011-3 Motherboard X99A Godlike Gaming Carbon, e atx MSI PRO B760M-P Motherboard, Micro-ATX