Error after fresh install: "You need to load the kernel first"

I installed the latest Ubuntu "20.04 LTS" on my machine, the installation was successfully and without any error.
The problem is that after the installation when the system starts, during the boot I get this error message "You need to load the kernel first" after the grub.
This error message seems to appear randomically, more often when I do a reboot using sudo reboot now or halt --reboot or rebooting via GUI and when the system is shutted down and I start it normally pressing the power button. Other times the system boots normally and the OS is ok, I can use it and there are no issue.

• Tried different times reinstalling the OS re-downloading the ubuntu image and using different tools in order to create the botable key (rufus, dd, balena etcher, ubuntu disk creator).
• Tried to reinstall the system using no network and disabling thirdy part additional components.

I'm on a Dell Inspiron and secure boot is disabled and the system is not a dual boot, there's only one ssd with a single instance of Ubuntu installed on it.

uname -a

Linux machine 5.4.0-52-generic #57-Ubuntu SMP Thu Oct 15 10:57:00 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux

lshw

============================================================
                                  system         Inspiron 5593 (097C)
/0                                bus            09PY2G
/0/1                              memory         1MiB BIOS
/0/400                            processor      Intel(R) Core(TM) i7-1065G7 CPU @ 1.30GHz
/0/400/701                        memory         128KiB L1 cache
/0/400/702                        memory         2MiB L2 cache
/0/400/703                        memory         8MiB L3 cache
/0/700                            memory         192KiB L1 cache
/0/1000                           memory         16GiB System Memory
/0/1000/0                         memory         8GiB SODIMM DDR4 Synchronous 2667 MHz (0,4 ns)
/0/1000/1                         memory         8GiB SODIMM DDR4 Synchronous 2400 MHz (0,4 ns)
/0/100                            bridge         Intel Corporation
/0/100/2                          display        Iris Plus Graphics G7
/0/100/4                          generic        Intel Corporation
/0/100/14                         bus            Ice Lake-LP USB 3.1 xHCI Host Controller
/0/100/14/0      usb1             bus            xHCI Host Controller
/0/100/14/0/1                     bus            SMC9514 Hub
/0/100/14/0/1/1                   generic        LAN9514
/0/100/14/0/1/4                   input          Trust Keyboard
/0/100/14/0/1/5                   input          USB Optical Mouse
/0/100/14/0/5                     generic        FingerPrint
/0/100/14/0/6                     multimedia     Integrated_Webcam_HD
/0/100/14/0/a                     communication  Bluetooth wireless interface
/0/100/14/1      usb2             bus            xHCI Host Controller
/0/100/14.2                       memory         RAM memory
/0/100/15                         bus            Ice Lake-LP Serial IO I2C Controller #0
/0/100/15.1                       bus            Ice Lake-LP Serial IO I2C Controller #1
/0/100/16                         communication  Management Engine Interface
/0/100/17                         storage        Ice Lake-LP SATA Controller [AHCI mode]
/0/100/19                         bus            Ice Lake-LP Serial IO I2c Controller #4
/0/100/1c                         bridge         Ice Lake-LP PCI Express Root Port #5
/0/100/1c/0                       display        GP108M [GeForce MX230]
/0/100/1d                         bridge         Ice Lake-LP PCI Express Root Port #9
/0/100/1d/0      enp2s0           network        RTL810xE PCI Express Fast Ethernet controller
/0/100/1d.1                       bridge         Intel Corporation
/0/100/1d.1/0    wlp3s0           network        QCA9377 802.11ac Wireless Network Adapter
/0/100/1d.4                       bridge         Intel Corporation
/0/100/1d.4/0                     storage        SK hynix
/0/100/1f                         bridge         Ice Lake-LP LPC Controller
/0/100/1f.3                       multimedia     Smart Sound Technology Audio Controller
/0/100/1f.4                       bus            Ice Lake-LP SMBus Controller
/0/100/1f.5                       bus            Ice Lake-LP SPI Controller
/0/0                              system         PnP device PNP0c02
/0/2                              system         PnP device PNP0b00
/0/3                              generic        PnP device INT3f0d
/0/4                              input          PnP device PNP0303
/0/5                              generic        PnP device DLL097c
/0/6                              system         PnP device PNP0c02
/0/7                              system         PnP device PNP0c02
/0/8                              system         PnP device PNP0c02
/0/9                              system         PnP device PNP0c02
/1                                power          DELL 1VX1H99
/2                                power          To Be Filled by O.E.M.
/3               enx00800fb03770  network        Ethernet interface

lsblk

NAME        MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
nvme0n1     259:0    0   477G  0 disk 
├─nvme0n1p1 259:1    0   512M  0 part /boot/efi
└─nvme0n1p2 259:2    0 476,4G  0 part /

Tell me if you need other infos about the OS or the HW.

EDIT If someone is still interested I still want to share info about this.
I didn't found a way to fix the error so I tried to reinstall the OS being sure of using UEFI mode, I followed the official guide by dell, but after the installation process the error was still present. The only way I found to fix the error is entering the BIOS and selecting my nvme as first boot option, disabling the entry relative to ubuntu. Don't ask ehy, I don't know, but now I'm using the system without troubles for months.