Missing RAM

I have a laptop with 8GB RAM (reported in UEFI) and have installed Ubuntu 20.04. However for some reason, only ~6GB is being shown.

Code:$ cat /proc/meminfo | head
MemTotal: 6024052 kB
MemFree: 1956944 kB
MemAvailable: 3836064 kB
Buffers: 176120 kB
Cached: 1886708 kB
SwapCached: 304 kB
Active: 2063388 kB
Inactive: 1400092 kB
Active(anon): 1196820 kB
Inactive(anon): 252976 kB
$
$
$
$ sudo dmidecode -t memory
[sudo] password for xxxxx:
# dmidecode 3.2
Getting SMBIOS data from sysfs.
SMBIOS 3.1.1 present.

Handle 0x0001, DMI type 16, 23 bytes
Physical Memory Array
Location: System Board Or Motherboard
Use: System Memory
Error Correction Type: None
Maximum Capacity: 12 GB
Error Information Handle: 0x0000
Number Of Devices: 2

Handle 0x0008, DMI type 17, 40 bytes
Memory Device
Array Handle: 0x0001
Error Information Handle: 0x0007
Total Width: 64 bits
Data Width: 64 bits
Size: 4096 MB
Form Factor: SODIMM
Set: None
Locator: DIMM 0
Bank Locator: P0 CHANNEL A
Type: DDR4
Type Detail: Synchronous Unbuffered (Unregistered)
Speed: 2400 MT/s
Manufacturer: Hynix
Serial Number: 21446EF3
Asset Tag: Not Specified
Part Number: HMA851S6DJR6N-XN
Rank: 1
Configured Memory Speed: 2400 MT/s
Minimum Voltage: 1.2 V
Maximum Voltage: 1.2 V
Configured Voltage: 1.2 V

Handle 0x000B, DMI type 17, 40 bytes
Memory Device
Array Handle: 0x0001
Error Information Handle: 0x000A
Total Width: 64 bits
Data Width: 64 bits
Size: 4096 MB
Form Factor: SODIMM
Set: None
Locator: DIMM 0
Bank Locator: P0 CHANNEL B
Type: DDR4
Type Detail: Synchronous Unbuffered (Unregistered)
Speed: 2400 MT/s
Manufacturer: Micron Technology
Serial Number: 00000000
Asset Tag: Not Specified
Part Number: 4ATF51264HZ-2G6E!
Rank: 1
Configured Memory Speed: 2400 MT/s
Minimum Voltage: 1.2 V
Maximum Voltage: 1.2 V
Configured Voltage: 1.2 V

$ journalctl | grep -i "memory.*available"
Aug 04 16:14:16 xxxxxx kernel: Memory: 5819924K/6164272K available (14339K kernel code, 2397K rwdata, 4952K rodata, 2712K init, 4992K bss, 344348K reserved, 0K cma-reserved)
Aug 04 17:42:07 xxxxxx kernel: Memory: 5819876K/6164272K available (14339K kernel code, 2397K rwdata, 4952K rodata, 2712K init, 4992K bss, 344396K reserved, 0K cma-reserved)
Aug 04 17:42:42 xxxxxx kernel: Memory: 5819876K/6164272K available (14339K kernel code, 2397K rwdata, 4952K rodata, 2712K init, 4992K bss, 344396K reserved, 0K cma-reserved)
Aug 04 19:09:53 xxxxxx kernel: Memory: 5819876K/6164272K available (14339K kernel code, 2397K rwdata, 4952K rodata, 2712K init, 4992K bss, 344396K reserved, 0K cma-reserved)
Aug 04 19:11:02 xxxxxx kernel: Memory: 5819876K/6164272K available (14339K kernel code, 2397K rwdata, 4952K rodata, 2712K init, 4992K bss, 344396K reserved, 0K cma-reserved)
Aug 04 20:56:31 xxxxxx kernel: Memory: 5819876K/6164272K available (14339K kernel code, 2397K rwdata, 4952K rodata, 2712K init, 4992K bss, 344396K reserved, 0K cma-reserved)
Aug 05 11:12:18 xxxxxx kernel: Memory: 5819876K/6164272K available (14339K kernel code, 2397K rwdata, 4952K rodata, 2712K init, 4992K bss, 344396K reserved, 0K cma-reserved)
$
$
$
$ top
top - 11:58:46 up 46 min, 1 user, load average: 0.92, 0.94, 0.96
Tasks: 251 total, 2 running, 249 sleeping, 0 stopped, 0 zombie
%Cpu(s): 1.5 us, 1.3 sy, 0.0 ni, 96.9 id, 0.3 wa, 0.0 hi, 0.0 si, 0.0 st
MiB Mem : 5882.9 total, 1889.3 free, 1805.1 used, 2188.4 buff/cache
MiB Swap: 8165.3 total, 8164.1 free, 1.2 used. 3744.6 avail MemSo as you can see, meminfo/top reports 6G however dmidecode shows I have 2 * 4GB modules.