CentOS 8, Dell PERC H330 RAID controller, no block device (most of the time)

We recently bought a New Dell R340XL Server and installed CentOS 8. We have one SSD for boot on the BOSS controller (as sda) and 4 HDDS on the PERC H330 in RAID 5 (as sdb). It worked fine for a few days, when two days ago, we could no longer see the RAID volume. We got on the phone with Dell, and they helped us upgrade firmwares on multiple devices, but still we can't see the RAID volume. Any help would be much appreciated.

The device shows up when I do lspci:

02:00.0 RAID bus controller: Broadcom / LSI MegaRAID SAS-3 3008 [Fury] (rev 02)
        Subsystem: Dell PERC H330 Adapter
...
        Kernel driver in use: megaraid_sas
        Kernel modules: megaraid_sas

I downloaded MegaCli, and I can get all kinds of information. The command MegaCli64 -LdGetNum -aAll tells me this:

Number of Virtual Drives Configured on Adapter 0: 1

If we reboot the server over and over again, once in a while, we'll see the RAID array appear as a block device, but it appears as sda, making the boot drive sdb.

I've looked through dmesg and system logs, and there's not much I know how to recognize, but I do see things like this:

[    1.296976] megasas: 07.707.51.00-rc1
[    1.301092] megaraid_sas 0000:02:00.0: FW now in Ready state
[    1.301095] megaraid_sas 0000:02:00.0: 63 bit DMA mask and 32 bit consistent mask
[    1.301363] megaraid_sas 0000:02:00.0: firmware supports msix        : (96)
[    1.301364] megaraid_sas 0000:02:00.0: current msix/online cpus      : (12/12)
[    1.301365] megaraid_sas 0000:02:00.0: RDPQ mode     : (disabled)
[    1.301366] megaraid_sas 0000:02:00.0: Current firmware supports maximum commands: 928        LDIO threshold: 237
[    1.301477] megaraid_sas 0000:02:00.0: Configured max firmware commands: 927
[    1.303185] megaraid_sas 0000:02:00.0: FW supports sync cache        : No

…

[    1.680004] megaraid_sas 0000:02:00.0: FW provided supportMaxExtLDs: 0       max_lds: 32
[    1.680005] megaraid_sas 0000:02:00.0: controller type       : iMR(0MB)
[    1.680005] megaraid_sas 0000:02:00.0: Online Controller Reset(OCR)  : Enabled
[    1.680006] megaraid_sas 0000:02:00.0: Secure JBOD support   : No
[    1.680006] megaraid_sas 0000:02:00.0: NVMe passthru support : No
[    1.680007] megaraid_sas 0000:02:00.0: FW provided TM TaskAbort/Reset timeout        : 0 secs/0 secs
[    1.702120] megaraid_sas 0000:02:00.0: INIT adapter done
[    1.702121] megaraid_sas 0000:02:00.0: Jbod map is not supported megasas_setup_jbod_map 5371
[    1.728949] megaraid_sas 0000:02:00.0: pci id                : (0x1000)/(0x005f)/(0x1028)/(0x1f44)
[    1.728950] megaraid_sas 0000:02:00.0: unevenspan support    : yes
[    1.728950] megaraid_sas 0000:02:00.0: firmware crash dump   : no
[    1.728951] megaraid_sas 0000:02:00.0: jbod sync map         : no
[    1.729017] scsi host0: Avago SAS based MegaRAID driver
[    1.730804] scsi 11:0:0:0: Processor         Marvell  Console          1.01 PQ: 0 ANSI: 5
[    1.732057] scsi_alloc_sdev: Allocation failure during SCSI scanning, some SCSI devices might not be configured
[    1.732076] scsi_alloc_sdev: Allocation failure during SCSI scanning, some SCSI devices might not be configured
[    1.732094] scsi_alloc_sdev: Allocation failure during SCSI scanning, some SCSI devices might not be configured
[    1.732112] scsi_alloc_sdev: Allocation failure during SCSI scanning, some SCSI devices might not be configured
[    1.732131] scsi_alloc_sdev: Allocation failure during SCSI scanning, some SCSI devices might not be configured
[    1.732149] scsi_alloc_sdev: Allocation failure during SCSI scanning, some SCSI devices might not be configured
[    1.732167] scsi_alloc_sdev: Allocation failure during SCSI scanning, some SCSI devices might not be configured
[    1.732185] scsi_alloc_sdev: Allocation failure during SCSI scanning, some SCSI devices might not be configured
[    1.732206] scsi_alloc_sdev: Allocation failure during SCSI scanning, some SCSI devices might not be configured
[    1.732224] scsi_alloc_sdev: Allocation failure during SCSI scanning, some SCSI devices might not be configured
[    1.732242] scsi_alloc_sdev: Allocation failure during SCSI scanning, some SCSI devices might not be configured

That allocation failure looks concerning, but when I tried googling it, I didn't find much. One person was trying to do over 200 logical devices, but we're definitely not doing that here.

Thanks in advance.