Precision 7920 Tower, felxbay 2 and 3 not seeing new SSDs

We're trying to add 3 additional 4TB SSD, was able to setup the one for flexbay 1 but for some reason it does not see 2 and 3. Ive tried using RAID and AHCI, nothing shows in file explorer nor does it make the USB detection sound. Any ideas what im doing wrong? Thank you