After BIOS update OMV6 won't boot from USB

I installed OMV6 to a new sandisk 32gb USB drive. It was actually booting just fine for several days (I'm setting up a new system) I set it up so the bios booted from the USB drive and I was able to restart the machine and it would load omv6 automatically with no involvement from me. In short it was working as expected for several days with BIOS settings pretty much stock I just change the boot order so the USB with OMV6 was first. Then I updated the bios using the bios utility, the update itself went fine but now mb just won't boot from the USB drive despite it being the first option, choosing to boot it from BIOS doesn't work either (it brings me back to bios). Motherboard is Z590i aorus ultra. I disabled the usual suspects, namely secure boot and TPM, but that didn't make a difference. What other settings can I change so I can boot OMV again? I haven't installed Windows or anything, I simply did the bios update.

Quote from chente

Look in the bios for the boot configuration in uefi mode or legacy mode. You must escape from uefi mode.

In the forums I found people saying omv supported uefi since a couple of years back and it was working fine before so that wouldn't be the issue. In the end it seems the BIOS update screwed up the usb drive installation.. not sure how. I reinstalled omv6 in a different drive (same brand, model and size) and I was able to boot from it just fine.

Quote from chente

Bios can't ruin anything. Only the bios settings can do it.

It seems like a bios upgrade for this mb can. The bios used to tell me what was on the usb ("debian") so even if it couldn't boot it should still be able to tell me that. In any case no setting regarding UEFI or legacy was ever changed, not even after the installation was screwed up so it was all the same.

Quote from chente

Now we are already wasting time, but only so that it doesn't happen to you again next time. You updated the bios. After updating the bios the configuration returns to the default state. To leave it as it was before updating you must review all the settings. If the boot mode changed in the bios and you didn't return it to its previous settings that was the reason that USB stick wouldn't boot. If you changed that configuration now you could start the system again with that pendrive, try it.

Find out on Google about this.

Good luck.

You're more focused on pretending you were right (despite not being right) than reading what I'm actually saying so I'm setting the record straight in case someone else has this happen in the future. Since you live in this forum it might be useful in a future case. Again: I did not change bios mode to legacy or uefi, Gigabyte doesn't even automatically reset the bios settings for this MB after an update, they ask you to do it yourself.. which I did AFTER I had tried everything else in order to see if that helped in booting the drive (it didn't). It's not like I changed that much from stock settings anyways. I still have the old installation by the way (like I said earlier, but you aren't actually reading what I'm saying), I reinstalled OMV6 in a different one from the same pack of drives. MB has same settings, reinstalled USB boots normally, the USB drive with the old installation still doesn't. USB with the old installation seemingly has all the files but the bios update might have overwritten something in it (reinstalled drive is recognized by mobo as "debian", old installation drive just shows the brand name). My takeaway is that I should've disconnected all other usb drives from mb before the update, which in retrospective sounds like common sense but Gigabyte did not reference this in their documentation, their Q-Flash tool did not warn me about it either. For reference, I did fish out the settings to change to legacy mode (gigabyte calls it CSM on this mobo), it didn't help in booting the old installation either.